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Volume 56, 1926
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The Upper Cretaceous Ammonites of New Zealand.

[Read before the Wellington Philosophical Society, 7th October, 1924; received by Editor, 13th October, 1924; issued separately, 13th March 1926.]

Plates 1947.

Contents.

[The section below cannot be correctly rendered as it contains complex formatting. See the image of the page for a more accurate rendering.]

Page
Discovery 129
Geological Occurrence 130
Descriptions of Species—
Phylloceras nera Forbes 134
Phylloceras radiatum n. sp. 135
Phylloceras forbesianum d'Orb. 136
Phylloceras minimum n. sp. 137
Phylloceras bistriatum n. sp. 138
Vertebrites murdochi n. sp. 139
Gaudryceras propemite n. sp. 142
Gaudryceras particostatum n. sp. 143
Gaudryceras subsacya n. sp. 144
Gaudryceras politissimum Koss. 145
Gaudryceras crenatum n. sp. 146
Zelandites kaiparaensis n. sp. 147
Tetragonites epigonus Koss. 149
Tetragonites latus n. sp. 149
Tetragonites simplex n. sp. 150
Tetragonites margaritatus n. sp. 151
Pseudophyllites indra Forbes 152
Pseudophyllites whangaroaensis n. sp. 153
Baculites rectus n. sp. 154
Diplomoceras wakanene n. sp. 155
Oxybeloceras sp. 156
Ptychoceras zelandicum n. sp. 157
Acanthoceras ultimum n. sp. 158
Gunnarites inflatus K. & R. 160
Gunnarites zelandicus Marshall 161
Gunnarites nordenskjoldi K. & R. 162
Gunnarites antarcticus Stuart Weller 162
Madrasites sulcatus n. sp. 164
Madrasites multicostatus n. sp. 164
Madrasites regularis n. sp. 165
Madrasites fortior n. sp. 166
Jacobites anderssoni K. & R. 168
Jacobites angularis n. sp. 169
Jacobites minimus n. sp. 169
Jacobites whangaroaensis n. sp. 170
Jacobites waitapuensis n. sp. 170
Neomadrasites nodulosus n. sp. 171
Brahmaites rotundus n. sp. 173
Maorites tenuicostatus Marshall 177
Maorites densicostatus n. sp. 178
Maorites suturalis n. sp. 179
Puzosia angusta n. sp. 182
Parapuzosia brevicostata n. sp. 183
Parapuzosia ordinaria n. sp. 184
Tainuia aucklandica n. sp. 186
Parapachydiscus rogeri n. sp. 188
Nowakites denticulatus n. sp. 189
Hauericeras ngapuhi n. sp. 190
Schluteria rarawa n. sp. 192
Importance of Suture-line 192
Geographical Relationship 194
Geological Age of Circum-Pacific Cretaceous Ammonite Horizons 198
Stratigraphical Features of the Batley Series 201
Geological Age of the Batley Series 203
Comparison with other Cretaceous Circum-Pacific Districts—
India 204
Japan 205
California 206
British Columbia 206
Patagonia 206
Chile 207
Seymour Island 207
Fossils found with the Ammonites 207
Literature 208
Discovery.

In the year 1917 (49, p. 443) a brief statement was made of the occurrence of ammonites at Batley, on the Otamatea arm of the Kaipara Harbour, North Auckland Peninsula. Since that time several visits have been made to Batley, and to Bull's Point, a neighbouring locality on the Arapaoa arm of the harbour where similar beds occur and where many of the same species of fossils are found. The first party, in 1916, included Mr. J. A. Bartrum, Lecturer on Geology at the Auckland University College, and Mr. R. Browne. In 1919 and in 1922 further visits were made to Bull's Point, and in 1923 collections were again made at Bull's Point and at Batley. In addition, a few specimens were found by Professor Benson and Mr. Bartrum in 1920, and by Mr. Ferrar, of the Geological Survey, in 1923.

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The result of all these collections has been the revealing of a fairly extensive fauna. It consists of specimens of several species belonging to all the important groups of mollusca, a few brachiopods, and a variety of fish-scales. There are also the remains of five species of plants. Probably the most interesting portion of the collection is that consisting of ammonites. Up to the present time very few species of ammonites have been recorded from the Cretaceous of New Zealand, and, with the exception of three species recorded in the previous paper on Batley, all have been collected in the South Island. They were first mentioned by Hector, and have been classified in papers written by Woods (57, p. 34), Trechmann (56, p. 338), and Spath (54). The species hitherto recorded are as follows: Madrasites haumuriensis Hector, Madrasites sp., Gaudryceras jukesi Sharpe (Whit-eaves), Gaudryceras sacya Forbes, Grossouvrites gemmatus Huppe, Baculites cf. vagina Forbes, Kossmaticeras zelandicum Marshall, Kossmaticeras tenui-costatum Marshall, Madrasites bhavani Forbes, Lytoceras sp.

The latest reference to the Upper Cretaceous ammonites of New Zealand is that of Spath (53, p. 299):—

“The writer has lately recognized the presence in the Upper Senonian of New Zealand of Kossmaticeras (Madrasites) bhavani Stol. sp., and K. (M.) cumshewaense (? Whiteaves) Kilian and Reboul1, as well as of K. (Gunnarites) aff. bhavaniforme Kilian and Reboul, K. (Grossouvrites) gemmatum Huppe sp., and of Pseudophyllites (Tetragonites) sp. juv.2

“Footnote (1): Possibly close to the incompletely known K. (Madrasites) mcKayi Hector sp. (Catal. N.Z. Court, 1886, p. 57, text-fig. 19a, No. 4) (misspelt maeCoyi in Haug. Traite, 2, p. 1345), that Steinmann (loc. cit., 1895, p. 28) considered to belong probably to the group of K. (M.) aemilianum Stol. sp.”

“Footnote (2): In collections kindly sent by Mr. Henry Woods, F.R.S., and by Dr. Trechmann (see Geol. Mag., n.s., dec. 6, vol. 4, 1917, p. 338).”

In the following pages sixty species are recorded, and all are described. This is done even when the specimens are identified as species already described from other countries, a practice adopted for the following reasons: (1) The literature in which the descriptions of these Upper Cretaceous ammonites have been published is very scattered and most difficult to obtain in New Zealand; (2) the distinction of the different species is carried to such a degree of refinement that the identifications made in this paper may be questioned by workers elsewhere, and in such cases it is well to have a description and a figure to which reference can be made; (3) the great distances between some of the countries where a few of the species have been recorded, and the absence of actual specimens for comparison, make identification difficult and even hazardous.

Geological Occurrence.

The formation in which the fossils occur is an unctuous mudstone which becomes arenaceous in places and even conglomeratic, and it contains many concretions varying in size from 5 ft. in diameter downwards. The great majority of the fossils have been found in the concretions, which are sometimes composed of spherical aggregates of calcite crystals—“pseudopisolitic”—and often show on the exterior an extremely well developed layer of cone-in-cone structure. The development of these structures has sometimes obscured certain features of the fossils, and in particular the suture-lines are occasionally hard to follow. The matrix of the specimens is also extremely hard, and the fossils are often fractured while they are being extracted. On the other hand, much of the shell matter remains, and in the great majority of instances the suture-lines are remarkably clear and easy to follow.

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The thickness of the formation in which the fossils are found is difficult to estimate. On the foreshore of the harbour where the strata occur the whole outcrop is covered with debris, for the unctuous nature of the rock allows of earth-sliding to an unusual degree, and it is rarely that any portion of the cliff-face can be seen. Above the immediate shore-line the whole surface of the hill is covered with vegetation, which effectually con ceals the rock from observation. Here and there, where a small exposure is visible, the strata stand at a high angle. The average direction of the strike at Bull's Point is 285°, and at Batley 295°. In both localities the ammonite-bearing strata are succeeded by a fine-grained chalky limestone, composed for the most part of tests of Globigerina—the so-called “hydraulic limestone” (49, p. 440).

At Bull's Point there are occasional nodules of barite, and frequently boulders of the lower part of the hydraulic limestone are thickly impregnated with black manganese oxides. Concretions of pyrite, also, are of frequent occurrence; and in the interior of many of the concretionary boulders of the ammonite beds, which are often septarian in nature, it is not unusual to find well-developed crystals of calcite. It is often found that a portion of the hydraulic limestone is siliceous and even flinty. This is probably due to the presence of siliceous organisms such as diatoms, radiolaria, and sponge-spicules, the occurrence of which has been reported by Marshall in similar material obtained from neighbouring localities (49, p. 434). Manganese dioxide, barite, and pyrite are found in far greater abundance on the northern shore of the Pahi arm, near Mr. Blackwell's house. Mr. Blackwell was good enough to point this out. A similar association is found on the eastern shore of the inlet behind the Batley Peninsula. In all these instances the occurrence of the minerals seems to be in the material near the base of the hydraulic limestone.

At Whangaroa the strata that contain the fossils are very similar to those at Bull's Point; but they appear to lie directly beneath the Wairakau breccia of Bell and Clarke (47, p. 65). No actual contact of the two formations could, however, be observed. The geology of this district was first described by McKay in 1892, but he did not collect any Upper Cretaceous fossils on the Whangaroa, except specimens of the genus Inoceramus (18, p. 68). He does, however, record ammonites as occurring in concretions in the south branch of the Kaeo River, In 1875 Mr. R. Bell, who then lived on the north side of the Whangaroa Harbour, near Totara North, sent several specimens to the Auckland Museum. Among these is a poor specimen of Gaudryceras kayei Forbes, and an excellent specimen of Tainuia multispinosa n. sp., which has also been found at Bull's Point. There is also a specimen of Phylloceras minimum n. sp., numbers of which have been found in the Kaipara localities. Bell's specimens probably came from the south side of the harbour, for in his letter to the curator of the Museum he says that the specimens in “sandstone” came from the south side of the river. Though “sandstone” is not a correct term to apply to the matrix of the specimens, it is certainly more nearly correct than “shale”—the only other material mentioned by Bell. The matrix is very similar to that of the fossils since obtained on the south side of the harbour. On both sides of the harbour concretions have been much used for roadmaking, and at the present time few of them can be found except at Nedler's Point, near the head of Waitapu Bay, about 200 yards distant from the road.

Clarke in 1909 (47, p. 56) stated that the concretions at Nedler's Point contained numbers of fossils, though the specimens he collected were few

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änd in bad preservation. However, he definitely stated that ammonites could be found in the concretions at Nedler's Point and made it possible for subsequent collectors to obtain specimens easily. In April, 1923, a considerable number of fossils, which are described in the following pages, were found in the concretions at Nedler's. Their nature and geographical occurrence will be discussed after the species in the whole collections have been recorded and described. The outcrop of rock is small, and perhaps rather less unctuous than at the Kaipara localities, but otherwise there is little difference. There are not many concretions to be found, but a larger proportion of them is fossiliferous than at Batley and Bull's Point. On the north side of the harbour there are now no concretions remaining, and no ammonites were found by me, but a few large masses of limestone contained numerous fragments of Inoceramus and specimens of another large species of pelecypod.

In addition to the localities mentioned above, Mr. Ferrar, of the Geological Survey, has recently collected specimens of ammonites at Te Opu, which is quite close to Bull's Point. None of the species found there are different from those found at the latter locality. He also found a few species at Matakohe, about six miles to the north-west. There are also a number of specimens of Vertebrites murdochi in the Auckland Museum. These were obtained at Hokianga, though the exact locality is not recorded. In the same place there is also a good specimen of Baculites rectus and one of Gaudryceras semileve, said to have been found at Morant's Island, in the Kawhia Harbour. This is probably an error, for Morant's Island is composed entirely of a glauconitic limestone, containing a great number of Tertiary fossils, whereas the matrix of the ammonite specimens is a shale. It is possible that “Kawhia” is a lapsus calami for “Kaipara.”

In the collection of the Geological Survey there are two ammonites collected by McKay at Awanui, near the East Cape; but subsequent collectors have failed to find any additional specimens. The two species are similar to some found at Bull's Point. One is close to Zelandites kaiparaensis, and the other is probably Schluteria rarawa. Ongley has recently found a small ammonite at the Pourere Beach, about forty miles south of Napier, but unfortunately it is not in a condition that admits of identification. He has also found a few impressions of ammonites near Whatatutu, inland from Gisborne.

All these localities are shown on the accompanying map, and it is evident that we now have definite information of the occurrence of a considerable extent of Upper Cretaceous strata in which ammonites have been found. There is reason to hope that a large fauna will ultimately be discovered. A map of the Kaipara will be found in 49, p. 435, and a map of Whangaroa in 47, map 3.

I wish to record my grateful thanks to the following institutions and friends: To the authorities of the South Kensington Natural History Museum, for giving me the use of a room and for allowing me to use their vast collections for comparisons; to the authorities of Victoria University College, Wellington, for giving me the use of a room in which to do my research; to the New Zealand Institute, for allowing me a grant of £40 from the Hutton Fund, and one of £50 from the Research Grant, to defray some of the expenses incurred. The following gentlemen have materially assisted me in collecting material: Mr. J. A. Bartrum, Lecturer on Geology, Auckland University College; Professor Cotton, Victoria College; both

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of these gentlemen kindly allowed me to use the resources of their laboratories. Mr. R. Brown and Mr. W. Blackwell also assisted me most materially in making the collections, and R. Marshall also added important specimens. Dr. L. Spath and Professor W. Kilian kindly examined many of my specimens and gave me most valuable advice. Dr. J. Marwick kindly copied drawings of the cross-sections for publication. The Australian Museum generously granted me a long loan of Kossmat's work; this is out of print and there are no copies in New Zealand.

Picture icon

Sketch-Map of New Zealand, showing Outcrops of fossiliferous rocks of upper cretaceous age.

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Descriptions of Species.

Dimensions.—In all cases the first column under each species gives the actual measurement; the second column gives the proportional measurement, assuming the diameter to be 100 mm.

All dimensions are given in millimetres, and all types, except four—Maorites tenuicostatus, Gunnarites zelandicus, Oxybeloceras sp., Tainuia aucklandica—are at present in my collection.

Phylloceras Suess.

Phylloceras nera Forbes. (Plate 19, fig. 4; Plate 26, figs. 1, 2.)

Compare—

1845.

Phylloceras nera Forbes (1, p. 106, pl. 8, fig. 7).

1885.

Phylloceras velledae Mich., in Stol. (11, p. 116).

1895.

Phylloceras nera Forbes, in Koss. (28, p. 109, Taf. 16, fig. 2 a—d).

1906.

Phylloceras sp. Woods (57, p. 331, pl. 41, fig. 4).

1907.

Phylloceras nera Forbes, in Paulcke (42a, p. 3, Taf. 14, fig. 5 a, b, c).

1921.

Phylloceras nera Forbes, in Spath (59, p. 40).

1921.

Phylloceras woodsi van Hoepen (52, p. 3, pl. 2, figs. 1–6, text-fig. 1).

1922.

Phylloceras woodsi van Hoepen, in Spath (54, p. 117).

Dimensions:—

[The section below cannot be correctly rendered as it contains complex formatting. See the image of the page for a more accurate rendering.]

A. B. C. D. E.
Diameter 42 100 13 100 24.5 100 46 100 20 100
Height of last whorl 23 54 8 61 14.6 60 28 61 12 60
Width of last whorl 11 26 4 30 7.4 30 13.2 29 6 30
Umbilicus 6 12 2.3 17 2.0 8 2.8 6 1.5 8

A and B, Phylloceras nera Forbes, Bull's Point, Kaipara Harbour, N.Z.; C and D, Phylloceras woodsi van Hoepen (52, p. 4); E, Phylloceras nera Forbes, in Koss. (28, p. 160, Taf. 16. fig. 2, a–d).

Shell discoidal, slightly umbilicated. Whorls strongly involute, high and narrow with greatest thickness about one-third of height measured from umbilicus. Umbilical wall steep and passing gradually into flank, curve gradually increases, and finally periphery is almost a circular arc Umbilicus cannot be properly cleared but is evidently extremely narrow, and a very small portion of any of inner whorls is exposed.

Ornamentation: Numerous thin rounded ribs, twenty in number, on a length of 10 mm. of periphery when height of whorl is 12 mm. They are hardly visible near umbilicus, and have a slight bend forward, but soon straighten up and pass over periphery without any change. On lower part of flank are six conspicuous folds in a half-revolution. These are strongly marked at umbilicus and curve forward in the same way as ribs, but soon weaken, and disappear completely half-way up flank.

Suture-line does not materially differ from that of P. nera figured by Kossmat; but in the largest specimen only five saddles can be distinguished, though in a smaller specimen, in which the details are less clear, eight saddles can be distinguished. The excellent preservation of the large specimen allows all the details to be seen where the whorl height is 19 mm. Owing to the shortness of the external lobe and the large development of the external branch of the first lateral lobe, the overlapping and inclined nature of the first lateral saddle is well shown. This feature was recorded by van Hoepen in the suture-line of Phylloceras woodsi.

The umbilicus of this species is wider than that of P. nera from Patagonia and of P. woodsi of Pondoland, and in addition there are twice as many folds as in the last species. The umbilicus is smaller than in P. decipiens Koss. This species differs from P. velledae in its more compressed form, and the folds disappear more quickly than in P. surya. The suture-line, however, is more like that of P. surya than that of P. nera.

Four specimens have been found, but all are incomplete. It has been found at Bull's Point, Batley, and at Whangaroa.

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Phylloceras radiatum n. sp. (Plate 19, fig. 7; Plate 26, figs. 3, 4.)

Compare—

1835.

Ammonites velledae Mich., Mag. de Zool., pl. 35.

1840.

Ammonites velledae Mich., in d'Orb., Terr. Cret. T. I. Ceph. pl. 82.

1857.

Ammonites (Scaphites) ramosus Meek, Trans. Alb. Inst., vol. 4, p. 45.

1860.

Ammonites velledae Mich., in Pictet et Camp., Terr. Cret. Ste Croix, vol. 1, p. 268, pl. 36, fig. 8.

1864.

Ammonites ramosus Meek, in Gabb, Geol. Surv. Canada, Pal., vol. 1, p. 65, pl. 11, fig. 4; pl. 12, fig. 12.

1865.

Ammonites velledae Mich., in Stol. (11, p. 116, pl. 59, figs. 1, 4).

1865.

Ammonites ramosus Meek, in Gabb (3, p. 65, pl. 11, fig. 4: pl. 12, fig. 12).

1873.

Ammonites velledae Mich., in Schmidt, Kreidepetrefacten von Sachalin (Mem. Acad. St. Petersburg), p. 10, Taf. 1, figs. 3, 4.

1876.

Phylloceras ramosum Meek, in White. Bull. U.S. Geol. Surv., vol. 4, p. 372, pl. 5, fig. 1.

1879.

Ammonites velledae Mich., in Whiteaves (8, p. 103).

1890.

Phylloceras velledae, Mich., in Yokoyama (17, p. 177, Taf. 19, fig. 1).

1895.

Phylloceras ramosum Meek, in Steinmann (26, p. 80, Taf. 5, fig. 4 a, b).

1902.

Phylloceras ramosum Meek, in Anderson (33, p. 34).

1906.

Phylloceras velledae Mich., in Boule, Lemoine, and Thevenin, Ceph. Diego Suarez, p. 7, pl. 1, figs. 6, 10, 11.

1909.

Phylloceras (Schluteria) ramosum Meek, in Kilian and Reboul (46, p. 9, pl. 1, fig. 3).

1920.

Phylloceras umzambiense van Hoepen (51, p. 142, pl. 24, figs. 1, 2, 3).

1922.

Phylloceras umzambiense van Hoepen, in Spath (54, p. 117).

Dimensions:—

[The section below cannot be correctly rendered as it contains complex formatting. See the image of the page for a more accurate rendering.]

A. B. C. D. E.
Diameter 43 100 32 100 150 100 44 100 38 100
Height of last whorl 25 58 56 57 27 62 16 42
Width of last whorl 18 42 26 58 17 40 13 34
Umbilicus 2 5 9 6 2 5

A. Phylloceras radiatum n. sp., Kaipara Harbour, N.Z.; B, Phylloceras surya Forbes, in Stol. (11, p. 115, pl. 58, fig. 5); C, Phylloceras velledae Mich., in Stol. (11, p. 116, pl. 59, figs. 1–4); D, Phylloceras umzambiense van Hoepen (51, p. 142); E, Phylloceras velledae Mich., in Yokoyama (17, p. 177, pl. 19, fig. 1 a, b).

The dimensions show that this species is distinct, though it approaches D.

Shell discoidal, strongly involute, and higher than wide. Greatest thickness rather nearer to umbilicus than to external border. Flank has a uniform curve from umbilicus almost to median line. Umbilicus deep and extremely narrow.

Ornamentation: Numerous narrow ribs steeper in front than behind. They commence as extremely fine lines at bottom of umbilicus, and gradually increase in size towards external margin, when at a height of 12 mm. there are eighteen ribs on a length of 10 mm. of periphery. Within umbilicus they are curved strongly backwards, but on leaving it curve a little forward, but straighten half-way between umbilicus and periphery, which they cross without any curve. As far as can be seen, there are no interstitial ribs. A series of wide folds, twelve in a half-whorl, extend from umbilicus across periphery, but they lose somewhat in height as they approach periphery. There are four or five ribs on each of the folds, which do not curve like the ribs, but are strictly radial in their direction. The folds seem to be more pronounced on surface of body-chamber, but the specimens are too imperfect to be certain of this.

The dimensions given above show that the species is much wider than Phylloceras surya and a good deal narrower than P. velledae. In dimensions and form of whorl it approaches more closely to P. umzambiense than to any other species of which details are available. Umbilical wall not so steep as that of P. ramosum Meek in Steinmann, and the whorl appears rather wider than that of P. ramosum Meek in Kilian and Reboul.

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Suture-line a good deal less divided than in P. ramosum Meek in Steinmann, and less than that species in Kilian and Reboul as far as can be seen from their figure. It is, however, of a typical Phylloceratid type, rather more complex than that of P. velledae, and decidedly more so than the suture-line of Phylloceras ellipticum Koss., a species that it closely resembles in the details of ornamentation. Phylloceras radiatum clearly belongs to the velledae group of the genus, which persisted through all Upper Cretaceous times. The marked radial folding, combined with the form of the whorl and the nature of the costation, seem to me to distinguish it from all others. In the costation it comes nearer to P. ellipticum Kossmat; in the form of the whorl and the folding the closest species is P. umzambiense; while in the development of the suture-line it lies between P. ramosum and P. velledae.

The internal portion of the suture shows only three saddles. The only figures available for comparison are those given in Zittel's Handbuch, vol. 2, p. 436. Here the line of a Dogger species is shown, but it has six saddles. It is interesting to note that Sowerbyceras has three saddles.

One good specimen and two fragments from Bull's Point, and one fragment from Whangaroa.

Phylloceras forbesianum d'Orbigny. (Plate 19, fig. 6; Plate 27, figs. 3, 4.)

Compare—

1845.

Ammonites rouyanus d'Orb., in Forbes, Geol. Soc. Lond., ser. 2, vol. 7, pl. 8, fig. 6, p. 108.

1850.

Ammonites forbesianus d'Orb., Prodrome, vol. 2, p. 13.

1865.

Ammonites rouyanus d'Orb., in Stol. (11, p. 117, pl. 59, figs. 5–7).

1890.

Phylloceras ezoense Yokoyama (17, p. 178, pl. 19, fig. 1 a–c).

1895.

Phylloceras forbesianum d'Orb. and P. whiteavesi Koss., in Kossmat (28, p. 109, pl. 15, fig. 1; also p. [189]).

Dimensions:—

[The section below cannot be correctly rendered as it contains complex formatting. See the image of the page for a more accurate rendering.]

A. B. C. D. E.
Diameter 25 100 18 100 13 100 14.5 100 28 100
Height of last whorl 15 60 12 66 8.2 63 8.5 58 18 64
Width of last whorl 15 60 12 66 8.2 63 9 62 17 61
Umbilicus 1 04

A, Phylloceras forbesianum d'Orb., in Koss. (28, p. 109, pl. 15, fig. 1 a–d); B, C, D, E, Phylloceras forbesianum, Bull's Point, Kaipara Harbour, N.Z.

Whorls rapidly increasing and extremely involute, so that umbilicus is practically obscured. Height and width almost equal, and cross-section almost circular. This is the same as in dimensions of P. forbesianum given by Kossmat, though the figure shows a far greater height than width. The whorl rises at first steeply from umbilicus, but curves uniformly in circular arc and has its widest part about half-way between umbilicus and periphery.

Ornamentation: Comparatively little of the material of the shell remains, but this shows a fine striation beginning on umbilical wall, at first bending backward strongly, but at half-way along flank it is succeeded by a bend forward; thereafter the striae become straight and cross periphery without a bend. After every seventh or eighth rib is a decided groove, most noticeable near umbilicus but becoming obscure on periphery.

Suture-line very similar to that given by Kossmat for Phylloceras forbesianum, though it is rather more complex and there is a far greater number of saddles, of which as many as twelve can be distinguished. These, of course, are very small in umbilical region, and they are much higher than wide. The external lobe is unusually deep. The external saddle is

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largest, and there is a uniform decrease in size as umbilicus is approached. This species differs from P. forbesianum in dimensions of whorl if Kossmat's figure is correct, though the measurements that he gives agree closely with those of this species. Suture-line of this species also is rather more developed than that of the Indian one. Yokoyama compares his species P. ezoense with P. forbesianum, but states rightly that the whorl is too high. His figure also suggests that the costation is too coarse.

Kossmat, in an appendix to his work on the Indian ammonites, separates the specimens which in the earlier part of his work he had classed together under P. forbesianum into two species, P. forbesianum and P. whiteavesi. Some of these specimens had come from the Utatur formation, of Cenomanian age, and others from the Valudayur beds, of Upper Senonian age. In the appendix he retains the former under the name of P. forbesianum, and establishes the species P. whiteavesi for the latter. The former species is somewhat more inflated and does not show the funnel form of the umbilicus so distinctly as the latter. In addition the saddles of the suture-line are larger, and the median saddle is simple and lancet-shaped, while in the two other occurrences (Valudayur beds of Pondicherry and the Nanaimo beds of Vancouver) it is strongly indented. He says that these are truly small distinctions, but they accord with different geological occurrences, so that great importance must be attached to them. He attaches great importance to the relation between the ultimate and penultimate whorls. In the specimens of P. forbesianum from the Utatur formation the relation in different specimens is 1: 2.75, 1: 2.5, 1: 2.6, while in a specimen of ezoense which is similar to P. whiteavesi it is 1: 3.2 (11, p. 124).

In this respect the New Zealand specimens are similar to P. forbesianum, for the relation is 1: 2.5 and 1: 2.25. In other words, the increase of the size of the whorls of the New Zealand species is less rapid than even that of the Utatur species. On the other hand, in the details of the suture-line there is a greater similarity to P. whiteavesi, for the median saddle is sharply indented and at the same time the saddles are relatively longer. It seems, then, that this species has some of the determining characters of each of the related Indian ones.

Several specimens, most of which come from Bull's Point, though others come from Batley and from Whangaroa.

Phylloceras minimum n. sp. (Plate 19, fig. 8; Plate 26, figs. 5, 6.)

Dimensions:—

[The section below cannot be correctly rendered as it contains complex formatting. See the image of the page for a more accurate rendering.]

A. B.
Diameter 13 100 8.5 100
Height of last whorl 7.5 57 5 58
Width of last whorl 7 54 4.5 53
Umbilicus

A, B, Phylloceras minimum, Kaipara Harbour, N.Z.

Shell small, highly involute, and, as dimensions show, height and width almost equal. Umbilicus obscured. There is a steep slope from umbilicus, and the greatest thickness is reached at a distance of about one-third of height from it, whence the curve is that of a circular arc over periphery. A series of fine hair-like striations commences at umbilicus, and at first are directed backwards; then they bend forwards and then straighten towards periphery, which they cross without any bend. They remain fine, but are much more distant on periphery.

The suture-line is highly developed when the size of the species is considered. The saddles are relatively long and well separated from one

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another. There is also a large number of auxiliary saddles. In this species, again, the internal portion of the suture-line has three saddles only. The internal saddle, as before, has the curious form characteristic of the genus.

This species is very similar to the last, but the ornamentation is far less distinct, and the whorl is wider. The suture-line also is more developed.

A number of specimens of this small species from Bull's Point and from Batley.

Phylloceras bistriatum n. sp. (Plate 19, fig. 5; Plate 27, figs. 1, 2.)

Compare—

1865.

Ammonites subalpinus d'Orb., in Stol. (11, p. 114, pl. 58, fig. 3).

1895.

Phylloceras ellipticum Koss. (28, p. 107, pl. 15, fig. 2).

1890.

Phylloceras ezoense Yokoyama (17, p. 19, pl. 2, fig. 178).

1921.

Phylloceras ezoense Yabe (61, p. 54, pl. 8, fig. 2).

Dimensions:—

[The section below cannot be correctly rendered as it contains complex formatting. See the image of the page for a more accurate rendering.]

A. B.
Diameter 43 100 25 100
Height of last whorl 27 63 15 60
Width of last whorl 22 51 15 60
Umbilicus 1 4

A, Phylloceras bistriatum n. sp., Bull's Point, Kaipara Horbour, N.Z.: B, Phylloceras forbesianum d'Orb., in Koss. (28, p. 109, Taf. 15, fig. 1).

A discoid highly involute form, with umbilicus reduced to smallest dimensions. Cross-section nearly circular, but there is a distinct angle at top of umbilical wall. The shell matter is poorly preserved, but it can be seen that interior whorls have an extremely fine, somewhat distant striation. On body-chamber there are in addition a number of large rounded ribs, which are narrow at umbilicus and gradually widen as they approach periphery, which they cross without change. The fine striations can be seen between and on the slopes of these large ribs.

Suture-line: Unfortunately only five of the saddles can be exposed. They are less finely divided than those of the other species, and the terminations are rounded and coarse. The secondary saddles in the lobes are but little divided.

So far as the suture-line is concerned, this species approaches most closely to the improvisum-ellipticum group in the Indian Lower Cretaceous fauna. It comes very close to P. ezoense Yokoyama (in Yabe, 1921).

A single specimen, in fair order, at Bull's Point.

Vertebrites n. gen.

It is considered necessary to establish this new genus because, though numerously represented by many specimens in splendid condition, it cannot be included in the genus Gaudryceras as emended by Kossmat (28, p. 113). The particular distinction is found in the internal portion of the suture-line, which shows six distinct saddles gradually decreasing in size from the antisiphonal line to the umbilicus. This condition is wholly different from that described by Kossmat as characteristic of Gaudryceras, which has a high single and narrow saddle in the internal portion of the suture-line. It may, of course, be maintained, as is suggested by Spath (53, p. 239), that such a development “is a result of the adaptation of a suture-line to wider sides.” This, however, does not seem to be a sufficient explanation in this instance, for the various species of the closely related

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genera Tetragonites and Pseudophyllites, in which the reduction of the sides is even more extreme than in the species of Gaudryceras, have an internal suture-line in which there are two well-separated saddles.

The species placed in this genus is clearly the New Zealand representative of the well-known and widely-distributed Indo-Pacific species Gaudryceras kayei Forbes. It seems, however, that the internal suture-line of that species has not yet been observed; and if, as seems probable, it should prove to be similar to that of Vertebrites murdochi it will have to be included in this new genus. It is not the suture-line alone that distinguishes these forms from the typical species of Gaudryceras: there is in addition the curious low and wide shape of the whorl, as well as the conspicuous difference in the ornamentation on the flanks as compared with that on the periphery.

The name Vertebrites is given to the genus because of the resemblance of a cross-section to that of a fish-vertebra.

Vertebrites murdochi n. sp. (Plate 20, figs. 9, 9a; Plate 30, figs. 1, 2; Plate 40, fig. 3.)

Compare—

1845.

Ammonites kayei Forbes (1, p. 101, pl. 8, fig. 3).

1865.

Ammonites kayei Forbes, in Stol. (2, p. 156, pl. 77, fig. 3).

1871.

Ammonites kayei Forbes, in Griesbach, Q.J.G.S., vol. 27, p. 63.

1879.

Ammonites jukesi Sharpe, in Whiteaves (8, p. 111, pl. 13, figs. 3 a, b, c).

1893.

Gaudryceras planorbiforme Bohm, in de Grossouvre (19, p. 231, pl. 27, fig. 2).

1895.

Lytoceras kayei Forbes, in Steinmann (26, p. 86, pl. 5, fig. 5).

1895.

Lytoceras (Gaudryceras) kayei Forbes, in Kossmat (28, pp. 124, 162, pl. 16, fig. 5; pl. 17, fig. 2).

1902.

Lytoceras (Gaudryceras) kayei Forbes, in Anderson (33, p. 83).

1909.

Lytoceras (Gaudryceras) kayei Forbes, in Kilian and Reboul (46, p. 12).

Dimensions:—

[The section below cannot be correctly rendered as it contains complex formatting. See the image of the page for a more accurate rendering.]

A. B. C. D. E. F. G.
Diameter 25 100 27 100 27 100 42 100 36 100 29 100 26 100
Height of last whorl 7 28 7 26 6.5 24 10.25 24 9 25 7.75 27 6.75 26
Width of last whorl 10.5 42 11 41 11 41 16 39 14 39 13 44 12.2 47
Umbilicus 14.5 58 14 53 15 55 25 60 21 58 16 55 14.8 57
H. J. K. L. M. N. P.
Diameter 29.8 100 30 100 31 100 28.8 100 30 100 26.2 100 10 100
Height of last whorl 7.0 24 7.4 25 7.2 23 7.2 24 6.9 23 5.9 23 2.2 22
Width of last whorl 11 37 11 37 13.2 43 12.6 43 13 43 11.8 45 5 50
Umbilicus 18 60 16 53 15.4 53 16.0 55 17 57 14.8 56 6.2 62
Q. R. S. T. V. W. X.
Diameter 22.5 100 58.5 100 12.6 100 30 100 57 100 46 100 24 100
Height of last whorl 6.5 29 18.5 32 3 24 8 27 19 33 15 33 8 33
Width of last whorl 9.5 33 18 31 5 40 10 33 18 32 15 33 9 37
Umbilicus 12.0 53 27.5 47 7 56 16 53 28 50 23 50 13 55

A, B, C, Vertebrites murdochi, Batley, Kaipara, N.Z.; D, E, F, G, H, J, K, L, M, P, Vertebrites murdochi, Whangaroa, N.Z.; N, Vertebrites murdochi, Hokianga, N.Z.; Q, Ammonites kayei Forbes, in Steinmann, l.c.; R, S, Gaudryceras kayei Forbes, in Koss., l.c.; T, V, W, X, Gaudryceras kayei Forbes: specimens in Kaye's collection in British Museum, Natural History Branch, South Kensington, London; measured by P. Marshall.

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These dimensions clearly show that the New Zealand specimens from three localities belong to the same species, and they differ from the typical Indian specimens in having a distinctly lower and also wider whorl and a slightly wider umbilicus. It might appear as though the dimensions of S contradicted this statement; but small specimens are all wider, and S should be compared with P.

Shell discoidal, with an involution of about one-third. Whorls much wider than high, with a surface rising steeply from umbilicus and passing with a gradually decreasing curve to periphery, where it is much flattened. The deep umbilicus has a steep slope almost uniform except for upper part of each whorl, which breaks the regularity with rather sharp curve. Whorls do not increase rapidly, and seven can be counted when shell has a radius of 10 mm. Strong sharp wire-like ribs start at bottom of umbilicus and are at first radial, directed slightly backwards; almost at once they curve strongly forwards, but become almost radial again on upper part of flank at point where covered by succeeding whorl. A little below this an interstitial rib generally appears between each pair of wire ribs, and at this line each rib usually breaks up into three fine striations. Other striations also take their origin at this level, though the original rib often continues straight on, but with the dimensions of one of the striations only. These striations at once bend forward and cross periphery with a gentle broad forward curve. On body-chamber the coarse wire ribs become much less numerous and are irregularly spaced, but the fine striations maintain their number and appearance.

The external portion of the suture-line is similar to that shown by Stoliczka for Gaudryceras kayei; Kossmat does not give a drawing of it. Six saddles can be distinguished, the external by far the largest. Auxiliary saddles much inclined, and with auxiliary lobes form a deep umbilical lobe. External lobe a little deeper than first lateral lobe. Internal portion of suture-line at once distinguishes the genus. Instead of the single lengthened saddle which is found in Gaudryceras, six distinct saddles can be seen. Of these the first, which is close to the antisiphonal line, is the largest and is bifid, though the division is not deep. The next saddle is shorter, and the size afterwards rapidly decreases to umbilicus. Second and third saddles are bifid. Antisiphonal lobe a little deeper than lobe next to it, but not nearly so deep as the decline of the whole suture-line on umbilical margin. Lobes all simply bifid.

The specimens that have been described show a close resemblance to the specimens of Gaudryceras kayei in the collection at the British Museum, Natural History Branch, at South Kensington. These are in the collection made by Kaye and described by Forbes. In the New Zealand specimens the periphery is somewhat flatter, sculpture coarser on umbilical surface, and finer on peripheral region, where also striae have a stronger forward bend. The width which Stoliczka mentions as so remarkable is still more marked than in the Indian specimens of the Kaye collection, though the measurements of the drawings given by Stoliczka show proportions almost exactly the same as in the New Zealand specimens. Yabe (37, p. 25) suggests that various specimens of G. kayei from South India, as well as Steinmann's specimens from Quiriquina, and the Griesbach specimen from South Africa, should be included in his species Gaudryceras tenuiliratum var, ornatum. The specimen of this species figured by him is, however, clearly a close relative of G. sacya, and quite different from the true

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G. kayei in form and sculpture. The specimen in the Griesbach collection has now rightly been recognized as a distinct species by van Hoepen, and he has named it G. varicostatum, which, as shown in this paper, is quite close to the New Zealand species G. semileve. G. jukesi Sharpe in Whiteaves (8) is certainly this species, and is quite different from the species that he refers to under G. jukesi later (27). There is no description of the forms identified by Anderson in California and by Kilian and Reboul in Seymour Island as G. kayei, but there is little doubt that they are typical forms of this species.

This species has been found at Batley and Bull's Point in the Kaipara, and plentifully at Whangaroa, where it seems to be the species called Desmoceras sp. by Clarke (47, p. 56, pl. 12, fig. 3 a, b).

Three specimens in the Auckland Museum come from Hokianga.

It is stated by Kossmat, and the remark is quoted by Kilian and Reboul, that G. kayei Forbes is closely related to G. planorbiforme Bohm from the Upper Cretaceous of Bavière. I have no specimens of this species for comparison, but, basing my opinion upon the description and figures given by de Grossouvre, I am unable to agree that the relationship is close. The specific name is given in memory of the late R. Murdoch, a well-known New Zealand conchologist.

Gaudryceras de Grossouvre (19, p. 225).

The following is the diagnosis of the genus given by de Grossouvre: “Ce genre est caracterisé par l'allure des striés de la coquille partant de l'ombili infléchies en avant, et par une ligne suturale formée de lobes et de selle assez nombreux, les lobes étant tous à terminaison paire.” He lays stress on the striae being directed back from the edge of the umbilicus. The sutural line is not so much reduced in auxiliaries as in Lytoceras. In the greater number of species the whorls increase slowly, and are but slightly involute in the young, but afterwards increase more rapidly, especially in height.

Kossmat later emended the description (28, p. 113). Slightly involute forms, with periodic constrictions forming bolsters on the shell or furrows on the cast. These, like the fine wire-like ribs, start at right angles to the umbilicus, and in the under half of the flank bend forward and in the upper half backward, forming a shallow forward bend on the periphery. The suture-line is of the greatest importance for the whole group. The median saddle is small, like a spear; the external lobe long and small, as deep as the first lateral lobe. The bifid external saddle is conspicuous. There are always several auxiliary lobes, which form a distinct umbilical lobe. In the internal portion there is a small and deep antisiphonal lobe, which goes as far back, or farther, than the umbilical lobe. A long tree-like saddle separates the two lobes, and on its side it is deeply dissected by sharp points. The bottom of the deep highly characteristic umbilical lobe is two-pointed, like the antisiphonal lobe. (Translation of extract.)

The nature of this internal suture-line separates Gaudryceras from Tetragonites. All species of Gaudryceras have at the base of the partition wall a single deep groove which corresponds in position to the antisiphonal lobe, while Tetragonites, with a greater number of internal lobes, has more than one on each side of the antisiphonal line.

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Gaudryceras propemite n. sp. (Plate 20, fig. 4; Plate 28, figs. 3, 4.)

Compare—

1865.

Ammonites sacya var. multiplexus Stol. (11, p. 155, pl. 76, fig. 1).

1866.

Lytoceras mite von Hauer, Neue Cephalopoden der Gosaugebilde, Sitz. Akad. der Wiss. Wien, Bd. 53, p. 7, Taf. 2, figs. 3, 4.

1873.

Ammonites sacya var. sachalinensis Schmidt (4, p. 15, Taf. 2, figs. 1, 2, 6.

1893.

Gaudryceras mite Hauer, in de Grossouvre (19, p. 227, pl. 26, fig. 4; pl. 39).

1895.

Gaudryceras jukesi Sharpe, in Whiteaves (27, p. 129, pl. 2, figs. 1, 2).

1895.

Lytoceras (Gaudryceras) multiplexum Koss. (28, p. 121, pl. 15, fig. 6).

1907.

Lytoceras varagurense var. patagonicum Paulcke (42a, p. 6, Taf. 17, figs. 1, 2).

1917.

Gaudryceras aff. jukesi (Whiteaves) Sharpe, in Woods (57, p. 35, pl. 20, fig. 2).

Dimensions:—

[The section below cannot be correctly rendered as it contains complex formatting. See the image of the page for a more accurate rendering.]

A. B. C. D.
Diameter 64 100 78 100 101 100 64 100
Height of last whorl 24 37 23 29 40 40 25 40
Width of last whorl 28 44 24 30 38 38 26 41
Umbilicus 19 30 38 49 35 35 24.5 39

A, Gaudryceras propemite, Bull's Point, Kaipara Harbour, N.Z.; B, Lytoceras (Gaudryceras) multiplexum Koss. (28, p. 121, Taf. 15, fig. 6); C, Lytoceras (Gaudryceras) varagurense (28, p. 122, Taf. 18, fig. 2, pl. 17, fig. 9): D, Lytoceras (Gaudryceras) vertebratum Koss. (28, p. 126, Taf. 15, figs. 4, 5).

The dimensions given above show that the breadth and height of the whorl are almost equal, and that they come nearest to G. vertebratum of the Indian species.

Form discoidal, with an involution of one-third. Seven whorls when diameter is 64 mm., with its greatest thickness just above slope to umbilicus; from this point there is a gradual slope to periphery, which is evenly rounded. Whorls slightly wider than high; whorls do not increase rapidly in height.

Ornamentation: A large number of rounded ribs of moderate size, which on body-chamber begin rather indistinctly near base of umbilical wall. They rapidly increase in distinctness, and at top of umbilical slope many divide into two, and other interstitial ribs arise, their number being increased about twofold. Ribs at first almost radial, but soon bend strongly forward, then distinctly backward, and at periphery again slightly forward so that they cross it with a slight forward curve. Ornamentation of inner whorls the same up to the point where they are covered by the next succeeding whorl; here they break up into striations, and similar additional striations arise interstitially and cross periphery with a slight forward bend. There are periodic furrows, sometimes very distinct, about four in a whorl.

Suture-line does not differ to any important extent from that of the different coarse-ribbed forms of Gaudryceras from South India which have been mentioned above. On the whole, it is rather more like that of G. vertebratum than the others. The most distinctive character is in the development of the median secondary saddle in the first lateral lobe.

The species is evidently very close to the G. vertebratum-varagurense group in all respects, but in none of them is there any mention of the curious change in the nature of the sculpture in all of the inner whorls. Gaudryceras cinctum Spath, from Pondoland, is also close, as is G. mite Hauer, from the Santonian of Europe. Again, G. varagurense var. patagonica Paulcke, from Patagonia, is closely related, but the details of the ornamentation seem to be distinct. G. varagurense and G. mite have been recorded by Kilian and Reboul from Seymour Island, but in both cases

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it appears that the state of preservation does not allow any details of the ornamentation to be seen.

A single complete specimen has been found at Bull's Point, as well as several fragments.

G. multiplexum and G. vertebratum come from the Utatur formation, and G. varagurense from the Upper Trichinopoly (= Lower Senonian) of Europe.

Gaudryceras particostatum n. sp. (Plate 20, fig. 7; Plate 30, figs. 3, 4.)

Compare—

1906.

Gaudryceras kayei Forbes, in Woods (40, p. 335, pl. 41, fig. 8).

1921.

Gaudryceras varicostatum van Hoepen (52, p. 7, pl. 2, figs. 10–12, text-figs. 3, 4).

1922.

Gaudryceras varicostatum van Hoepen, in Spath (54, p. 117).

Dimensions:—

[The section below cannot be correctly rendered as it contains complex formatting. See the image of the page for a more accurate rendering.]

A. B. C. D.
Diameter 27 100 24 100 33 100 39.6 100
Height of last whorl 10 37 9 38 13 39 13.7 35
Width of last whorl 10 37 9 38 11 34 14.7 37
Umbilicus 10 37 11 45 13 39 17.2 43

A, B, C, Gaudryceras particostatum, Bull's Point, Kaipara Harbour, N.Z.: D, Gaudryceras varicostatum van Hoepen (52, p. 7).

The dimensions show at once that height and width of whorl are almost equal, and umbilicus extremely wide. Shell small, with whorls that show little involution and do not increase rapidly in size. Umbilicus wide, with a nearly uniform slope. When the radius is 14 mm. six whorls are developed. The umbilical slope is steep, but passes by a rapid curve into the flank, which slopes steeply to the well-rounded periphery.

Ornamentation: Flanks of inner whorls covered with thin wire-like ribs, which begin at umbilicus and at once bend sharply forward. At edge of periphery, where whorl is covered by the succeeding one, the wires change into a number of minute striations, which require a high-powered lens to show them up. These have a slight bend forward where they cross periphery. On body-chamber the wire-like ornamentation cannot be seen, and its place is taken by fine striations; these are not easily seen, and without a careful inspection the surface appears to be smooth. Four conspicuous constrictions in a revolution.

Suture-line in both external and internal portions very similar to that of Gaudryceras varicostatum. Antisiphonal lobe differs from typical form in its greater breadth. External portion of suture-line is quite typical of the genus, though, on the whole, it is perhaps rather less deeply dissected. Umbilical lobe unusually deep and extremely steep. The width of the single saddle in the internal portion of the suture-line is noticeable, and in this respect this species resembles G. propemite, G. varicostatum, and G. varagurense, though it is less marked in the last species.

This species certainly comes nearer to Gaudryceras varicostatum than to any other that could be found in the available literature. It is, however, distinguished by the finer ribbing and the somewhat higher whorl. There seems to be no Indian species to which it shows a close resemblance, for it has a higher whorl and smaller umbilicus than G. multiplexum; finer ribbing and a wider umbilicus than G. varagurense; a narrower and lower whorl than G. vertebratum, and finer ribbing as well; and in none of these species has it been recorded that the ribbing changes in its character on the upper part of the flank.

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Several good specimens have been obtained at Bull's Point, and one in poor condition from Whangaroa. In the Auckland Museum there is a specimen in good condition labelled as coming from Morant's Island, in the Kawhia Harbour. This, however, I regard as a mistake, as the rocks on that minute island are entirely Tertiary in their age. It is possible that this and Baculites rectus n. sp., which have the same matrix, come from Hokianga or from Kaipara.

Gaudryceras subsacya n. sp., (Plate 20, figs. 8, 8a; Plate 29, figs. 1, 2.)

Compare—

  • Ammonites sacya Forbes (1, p. 113, pl. 14, fig. 10).

  • Ammonites buddha Forbes (1, p. 112, pl. 14, fig. 9).

  • Ammonites sacya Forbes, in Stol. (11, p. 154, pl. 75, figs. 5–7; pl. 76, figs. 1, 2, 3).

  • Ammonites sacya var. sachalinensis Schmidt (4, p. 15, pl. 2, figs. 3, 4).

  • Ammonites filicinctus Whiteaves (7, p. 43, pl. 2, figs. 2, 3).

  • Lytoceras sacya Forbes, in Whiteaves (7, p. 203, pl. 25).

  • Lytoceras sacya Forbes, in Yokoyama (17, p. 178, pl. 18, fig. 12).

  • Lytoceras sacya Forbes, in Jimbo (22, p. 34, pl. 6, fig. 1).

  • Lytoceras sacya Forbes, in Stanton (20, p. 445).

  • Lytoceras (Gaudryceras) sacya Forbes, in Koss. (28, p. 119).

  • Lytoceras (Gaudryceras) sacya Forbes, in Anderson (33, p. 82).

  • Gaudryceras tenuihratum Yabe (48, p. 19, pl. 3, figs. 3, 4; also var. ornata, pl. 3, fig. 2).

  • Gaudryceras striatum var. pictum Yabe (48, p. 33, pl. 4, fig. 3).

  • Gaudryceras sacya Forbes, in Woods (57, p. 11, pl. 5, figs. 4 a, b).

  • Lytoceras sp. Marshall (49, p. 445, pl. 33, fig. 3, text-fig. 4).

  • Gaudryceras sacya Forbes, in Spath (59, p. 54).

Dimensions:—

[The section below cannot be correctly rendered as it contains complex formatting. See the image of the page for a more accurate rendering.]

A. B. C. D. E. F. G.
Diameter 28 100 22.75 100 36 100 29 100 24 100 16 100 45 100
Height of last whorl 10.5 37 9 39 12.5 35 11 38 9 37 6.2 39 33
Width of last whorl 10.75 42 10.25 45 14 39 12 41 10.25 42 8 50 34
Umbilicus 11.5 41 10 44 13.5 38 11.25 39 9 37 7 44 44
H. J. K. L. M. N. P.
Diameter 95 100 40 100 50 100 120 100 113 100 300 100 35 100
Height of last whorl 43 30 34 40 50 44 160 53 12 34
Width of last whorl 36 35 30 38 45 40 165 53 13 38
Umbilicus 32 50 46 36 36 32 55 18 15 42

A, B, C, D, E, F, Gaudryceras subsacya, Bull's Point and Batley, Kaipara Harbour, N.Z.; G, H, J, K, L, Gaudryceras sacya Forbes, in Stolicka (11, p. 154, pl. 75, figs. 5–7; pl. 76, fig. 23); M, Gaudryceras sacya Forbes, in Kossmat (28, p. 119); N, P, Gaudryceras tenuiliratum Yabe (37, p. 19).

The six specimens of G. subsacya that were measured show at once that the species always has a whorl that is wider than high, and that the larger specimens are both lower and narrower than smaller ones. The Indian specimens that were measured by Stoliczka are in most cases higher than wide, and this is also the case in the Indian specimen quoted by Kossmat. Yabe's measurements of Gaudryceras tenuiliratum are much higher and wider in the large specimens than in the smaller. The measurements show that species is characterized by its uniformly wide whorl.

Shell discoidal with wide umbilicus, downward slope of which is modified by rounded contour of inner whorls. Involution about one-third. Slope from umbilicus steep, and gradually rounds off into flank; periphery flattened. Well-preserved specimens show five distinct constrictions marked

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on shell by prominent rounded ribs, which have a large furrow behind and a smaller one in front. Regular sculpture consists of extremely numerous ribs, so fine that when radius is 7 mm. there are 45 on an arc of periphery 5 mm. in length. Large ribs that mark constrictions are covered with these fine ribs, which arise at bottom of umbilical slope and at first have a slight forward inclination. This soon becomes pronounced, but decreases again at about two-thirds of distance from umbilicus. Ribs cross periphery with the very slightest forward bend. Near top of umbilical slope an interstitial rib arises between each pair, and all continue without interruption across periphery. Ribs and sculpture on body-chamber differ in no respect from those on younger whorls, except in size, which increases proportionately to diameter.

Suture-line is typical of the smaller species of Gaudryceras, and by itself can hardly be distinguished except by the slightly displaced position of the small secondary saddle in the first lateral lobe. Internal portion of suture-line also is quite typical of these smaller species, and shows the long and narrow single saddle which Kossmat considers an essential feature of the genus.

The position of this species is very close to G. tenuiliratum var. ornatum of Yabe; but comparison of the measurements shows that the whorl is both higher and wider than in the Japanese species, and at the same time the umbilicus is narrower. The resemblance to G. striatum var. pictum of Yabe is also close, but the ribs appear to be much more flexuous in that species. The specimens considered to be G. sacya by Yokoyama and Jimbo are differently classed by Yabe. Crick's specimen of G. pulchrum in the South Kensington Museum was also compared with those from New Zealand, and it was found that its ribs were distinctly sharper and farther apart than in the present species. Forbes's type of G. sacya is also in the Museum, and though it is in poor condition it is clear that the ribs are a little larger and farther apart than in the New Zealand examples. The species appears to be very similar to G. filicinctus of Whiteaves from the Queen Charlotte Islands. The examples here described from the north of New Zealand are quite close to the specimen from the Clarence Valley of the South Island of New Zealand, which was classified by Woods as G. sacya, for the only observable difference in that the ribs in the South Island specimen are rather coarser than those of all but one of the specimens from the North Island.

This species is common at Batley and at Bull's Point in the Kaipara Harbour, but no specimens were found at Whangaroa.

Gaudryceras sacya comes from the Lower Utatur group. No specimen yet found in New Zealand shows the corrugations which characterize the mature forms of G. sacya as figured by Whiteaves and of G. limatum figured by Yabe.

Gaudryceras politissimum Kossmat. (Plate 20, fig. 3; Plate 28, figs. 1, 2.)

Compare—

1895.

Gaudryceras politissimum Koss. (28, p. 128, Taf. 15, figs. 7 a-c).

1907.

Lytoceras (Gaudryceras) politissimum Koss., in Kilian and Reboul (46, p. 14, pl. 1, figs. 7, 8).

Dimensions:—

[The section below cannot be correctly rendered as it contains complex formatting. See the image of the page for a more accurate rendering.]

A. B.
Diameter 48 100 89 100
Height of last whorl 20 49 33 37
Width of last whorl 14 29 28 31
Umbilicus 16 33 34 38

A, Gaudryceras politissimum Koss., Bull's Point, Kaipara Harbour, N.Z.; B, Gaudryceras politissimum Koss. (28, p. 128).

– 146 –

These dimensions show that the only specimen that is in good enough condition to be measured has a whorl a little higher than that of Kossmat's type, while the umbilicus is distinctly narrower. Comparisons with the dimensions of G. subsacya show that the whorl in that species is not so high as, but is much wider than, that of G. politissimum. In the specimen that has been measured the greater part of outer whorl is somewhat compressed. The inner whorls increase a good deal in their relative width, the penultimate whorl measuring—height, 4.5 mm.; width, 5.5 mm.; and the whorl next to that—height, 2.5 mm.; width, 3.5 mm. The broadest part of outer whorl is at top of umbilical wall, where there is a sharp curve to the gently sloping flank; but at periphery the curve is much sharper.

Ornamentation: Five constrictions can be distinguished in the last whorl, which appear as rounded ribs on the shell. They are low where they leave umbilicus. They at once bend forward and increase in size, but the forward curve is soon reduced, and they cross periphery with a slight forward bend. At first sight the surface of the shell appears to be polished, but when examined with a lens a number of regular but extremely fine hair-like ribs can be distinguished. About every tenth or fifteenth of these is larger. They start almost straight from the umbilicus, or with a slight backward trend. They soon bend forward on the edge of umbilicus; then they straighten up, but pass over periphery with a broad forward curve.

Suture-line agrees fairly well with that of G. politissimum figured by Kossmat. The saddles, however, are less divided, the slope to umbilicus begins sooner, and there are fewer auxiliary saddles; umbilical lobe is also deeper.

The specimen agrees quite well with description that has been given by Kossmat, though the relative height and width of inner whorls are not referred to by him. The ornamentation and also the form of G. politissimum, G. subtilineatum Koss. (28, p. 123), and G. valudayurense Koss. (28, p. 127) are very similar, but it appears that the ornamentation of the surface of G. valudayurense is rather stronger and the suture-line is rather more divided. It would be extremely difficult to distinguish the inner whorls of the New Zealand specimen of G. politissimum from those of G. subtilineatum described by Kossmat.

One specimen, in moderately good condition, from Bull's Point, and a second, of the inner whorls only, from Batley.

Gaudryceras crenatum n. sp. (Plate 20, fig. 10; Plate 31, figs. 3, 3a.)

Dimensions:—

A.
Diameter 27 100
Height of last whorl 9 33
Width of last whorl 10 37
Umbilicus 12 44

A, Gaudryceras c [ unclear: ] enatum, Bull's Point, Kaipara Harbour, N.Z.

Shell discoidal, with wide umbilicus which has very even slope. Involution about one-third. A steep even slope of umbilical wall, which curves rather quickly into flank, and therafter a uniform curve which passes without interruption over rounded periphery.

Ornamentation: Four shallow periodic furrows in last whorl, with occasionally a low rounded rib behind. The surface appears bright and shining, but examination shows that it is closely covered with fine thread-like ribs. These arise at umbilicus and are at first straight, but soon bend

– 147 –

forward and maintain this direction until they reach beyond umbilical edge; they then bend slightly backwards, but soon again bend forward and pass with a broad curve across periphery. Ribs become less distinct at periphery, but there are no interstitial ribs. Ribs have a sharp crest, but are distinctly crenate on backward side. A good specimen and a high-power lens are necessary to reveal this structure.

Suture-line not well seen. Saddles not so highly divided as in the other species of Gaudryceras. External lobe is perhaps a little deeper than usual, and three auxiliary lobes are present.

Three specimens only, two of which come from Bull's Point and one from Batley.

The crenation of the small ribs is the most distinct characteristic of this species. So far as Cretaceous species of this family are concerned, it has been recorded only in Lytoceras mahadeva Stol., from the Lower Utatur of India; L. batesi, from the lower beds of Queen Charlotte Island of British Columbia; and L. ezoense, from the Lower Ammonite beds of Japan. These are included in the Lytoceras fimbriatum group of Kossmat, which is mainly distinguished by the absence of auxiliary lobes and saddles in suture-line (28, p. 112). The present species has three auxiliary lobes and saddles and at the same time its small size and fine ribbing ally it rather to the Gaudryceras group. It is perhaps permissible to regard the crenation as a vestigial remnant that shows clearly the lytoceratid ancestry.

Zelandites n. gen.

This genus is suggested for some ammonites that could not be placed in any of the genera of which detailed descriptions and literature were available. The ornamentation is so similar to that of several species of Gaudryceras that it seems necessary to place it close to that genus. The narrow and high whorl has the general form of that of Gaudryceras varuna, which has been recorded from Quiriquina by Steinmann as well as from its original locality. On the other hand, the suture-line, so far as its general appearance is concerned, and especially in the nature of the first lateral lobe, is so peculiar that it becomes doubtful if the species should be included in the Lytoceratidae. However, in the absence of specimens of allied species for comparison, and of more extensive literature, it has been placed here provisionally.

Zelandites kaiparaensis n. sp. (Plate 20, figs. 9, 9a; Plate 31, figs. 1, 2.)

Compare—

1845.

Ammonites varuna Forbes (1, p. 107, pl. 8, fig. 5).

1865.

Ammonites varuna Forbes, in Stol. (11, p. 111, pl. 58, fig. 1).

1894.

Desmoceras kawanoi Jimbo (22, p. 28, pl. 1, fig. 7 a, b).

1895.

Lytoceras (Gaudryceras) odiense Koss. (28, p. 129, pl. 18, fig. 1 a-c).

1895.

Lytoceras (Gaudryceras) varuna Forbes, in Koss. (28, p. 130, pl. 16, fig. 4 a-b: pl. 17, fig. 8).

1895.

Lytoceras varuna Forbes, in Steinmann (26, p. 84, Taf. 5, fig. 2 a, b; text-fig. 7).

1903.

Gaudryceras kawanoi Jimbo, in Yabe (37, p. 41).

Dimensions:—

[The section below cannot be correctly rendered as it contains complex formatting. See the image of the page for a more accurate rendering.]

A. B. C. D.
Diameter 25 100 18 100 23 100 26 100
Height of last whorl 12 48 8 44 12 53 13.5 52
Width of last whorl 7.45 30 6.5 35 7.5 33 7 27
Umbilicus 6.5 26 5 28 4.5 20 5.2 20

A, B, Zelandites kaiparaensis n. sp., Bull's Point, Kaipara Harbour, N.Z.; C, Lytoceras (Gaudryceras) varuna Forbes, in Koss. (28, p. 161); D, Lytoceras varuna Forbes, in Steinmann (26, p. 84).

– 148 –

The dimensions show a fairly close resemblance to Gaudryceras varuna, though the whorl of the New Zealand species is not so high and the umbilicus is a good deal wider.

Shell small, discoidal, with an involution of about two-thirds. The greatest width is just above umbilicus, to which the slope is steep, though it rounds off gradually at top of wall; thence the flanks slope gradually to periphery, which is narrow and sharply rounded. Body-chamber has the length of two-thirds of a revolution. Surface of inner whorls covered with fine hair-like ribs, at first strongly inclined forwards, but at top of umbilical slope they become straight and pass straight over periphery. Body-chamber has the same ornamentation as inner whorls. Nine deep constrictions in a whorl. They are at first radial in direction, but soon take a strong bend forward, and near periphery become radial again, passing over it with a barely noticeable backward curve. These constrictions are visible on the shell and have no ribs before or behind.

Suture-line peculiar, and the absence of much literature makes it hard to classify the species. The median saddle is sharp and has a few jags on side. External saddle high and bifid, with a much larger development on external than on internal side. The two lateral saddles are also bifid, but are much smaller, and seven auxiliary saddles can be distinguished. All divisions of the saddles have deep and sharp jags, which give rather a distinct appearance. External lobe about as deep as first lateral lobe, and rather wide. First lateral lobe wide, and the small secondary saddle in the middle is much less conspicuous and important than in Gaudryceras. There are larger projections on either side of it, and of these the internal one is by far the largest element in the whole. This is similar to the same lobe in Diplomoceras cylindraceum Defr. (47A, fig. 1259; 45, Taf. 45, fig. 47) and to that in D. wakanene, figured in this paper (Plate 19, fig. 3), but it is quite different from that in the four Indian species of Anisoceras Pictet = Diplomoceras Hyatt figured by Kossmat (28, Taf. 19). The other lobes present no unusual features. Auxiliary lobes and saddles highly inclined, and form a deep umbilical lobe. Internal portion of suture-line not much different from that of G. semileve or G. propemite, or of G. varicostatum van Hoepen, and approaches that of G. varagurense as drawn by Kossmat. In the three first-mentioned at least it may be said that there is a single wide and rapidly thinning saddle, which is high, while smaller saddles are represented by projections on its outer side. This is certainly distinct from the single thin and high saddle of G. subsacya and G. vertebratum as drawn by Kossmat.

The form of this species shows affinities with that of G. varuna and G. kawanoi, while the ornamentation is similar to the general characters of that of Gaudryceras.

Four specimens, all of them from Bull's Point, on the Kaipara Harbour. A specimen of a closely allied species is in the collection of the New Zealand Geological Survey. It was found by McKay at Awanui, near East Cape, in Cook County. It differs from the Kaipara form in ornamentation, as it is almost destitute of ribs, but in form and suture-line it differs but little.

Tetragonites Kossmat, 1895.

Whorls strongly involute and rapidly increasing. Cross-section trapezoidal, the broadest part near umbilicus: flanks and periphery flattened. Fine growth-lines only, and usually periodic growth forms bolsters on the shell and deep constrictions on the cast. Siphuncular saddle lance-shaped; external lobe same depth as first lateral lobe, which has a median secondary saddle. Several auxiliary saddles. Internal portion of suture-line may have

– 149 –

as many as four saddles, which are bifid like saddles of external portion. The genus begins with T. duvalianum in the Neocomian, and extends in a single Indian species into the Senonian.

The above is a brief summary of the generic diagnosis given by Kossmat (28, p. 131).

Tetragonites epigonus Kossmat. (Plate 21, fig, 10; Plate 29, figs, 6, 7.)

Compare—

1865.

Ammonites timotheanum Mayor, in Stol. (11, p. 146, pl. 73, fig. 5).

1895.

Lytoceras (Tetragonites) epigonum Koss. (28, p. 135, Taf. 17, figs. 4 a, b, c, 5 a, b).

1907.

Lytoceras (Tetragonites) epigonum Koss., in Paulcke (42A, p. 8).

1909.

Lytoceras (Tetragonites) epigonum Koss., in Kilian and Reboul (46, p. 14).

Dimensions:—

[The section below cannot be correctly rendered as it contains complex formatting. See the image of the page for a more accurate rendering.]

A. B. C. D.
Diameter 38 100 59 100 23 100 28 100
Height of last whorl 20 53 26 44 10 43 11 39
Width of last whorl 22 58 27 46 11 44 12 43
Umbilicus 8 21 15 25 7 30

A, Tetragonites epigonus Koss., Bull's Point, Kaipara Harbour, N.Z.; B, C, Lytoceras (Tetragonites) epigonum Koss. (28, p. 135); D, Lytoceras (Tetragonites) epigonum Koss., in Paulcke (42A, p. 8).

Shell discodial but whorls increasing rapidly in size. Involution about one-half, and umbilicus small but deep. Whorls wider than high. Umbilical wall almost vertical but soon curving rapidly into flank, which is gently rounded and passes without any sudden angle into periphery. Thickest part of whorl just above umbilicus. Surface appears smooth and polished, but examination shows it traversed by fine lines which arise radially on the steep slope of umbilicus, then bend forward, but soon change again and cross periphery with a slight curve backward. There are deep constrictions, most pronounced on middle of flanks but soon fade away towards periphery and in umbilicus; there are five in a revolution, and they follow the same general course as the striations.

Suture-line very similar to that of Pseudophyllites indra, and I fail to find any important differences in the figures given by Kossmat for the two species and also in the specimens found in New Zealand. The internal portion of suture-line shows a similarity to the figure of Kossmat, but the saddles are less divided and the saddle nearest to umbilical surface is relatively shorter.

One specimen at Bull's Point, and one at Batley.

Tetragonites latus n. sp. (Plate 20, figs. 6, 6a; Plate 32, figs. 1, 2.)

Compare—

1847.

Ammonites timotheanus Pictet and Roux; also the same species in. Stoliczka, Schmidt, Whiteaves. Anderson, and Kossmat.

1903.

Tetragonites glabrus Jimbo, in Yabe (37, p. 43, pl. 7, figs. 2, 5).

1907.

Tetragonites kingianum var. involutior Paulcke (42A, p. 9, Taf. 17, figs. 3 a, b, 4 a, b).

1921.

Tetragonites superstes van Hoepen (52, p. 11, pl. 2, figs. 17–20, text-fig. 6).

Dimensions:—

[The section below cannot be correctly rendered as it contains complex formatting. See the image of the page for a more accurate rendering.]

A. B. C. D. E. F.
Diameter 19 100 13 100 13.5 100 80 100 32.4 100 35 100
Height of last whorl 9.5 50 7 54 7.3 54 41 50 14.2 44 17 48
Width of last whorl 11 58 7.7 59 8 59 45 56 15.5 48 19 54
Umbilicus 3 16 2 16 2 15 16 20 8.3 26 8 21

A, B, Tetragonites latus, Bull's Point, Kaipara Harbour, N.Z.; C, Tetragonites latus, Batley, Kaipara Harbour, N.Z.; D, Tetragonites timotheanus Pictet, in Koss. (28, p. 133, Taf. 17, figs. 11, 13 a, b); E, Tetragonites superstes van Hoepen (52, p. 11, pl. 2, figs. 17–20, text-fig. 6); F, Tetragonites glabrus Jimbo, in Yabe (37, p. 43, pl. 7, figs. 2, 5).

– 150 –

Shell small, discoidal, somewhat inflated and involute. Four whorls only in a radius of 10 mm. Whorls rise very steeply from umbilicus, where there is a distinct rounded angle, and afterwards a uniform curve to periphery, which is slightly flattened. Whorls always distinctly wider than high, and increasing rapidly, thus forming a deep and narrow umbilicus.

Ornamentation: The surface is practically smooth, but longitudinal grooves can be seen distinctly. There is one on each side of the median line, about 1 ½ mm. distant from it in the largest specimen. There is another, less distinct, where the whorl curves from the flat periphery to the flank. These spiral lines are not distinct in all specimens.

Surface of shell appears to be bright and shining, but is actually marked by very fine indistinct and irregular striations, between which low rounded ribs can be distinguished. These bend forward slightly at first, then cross periphery without change. Spiral lines of a similar nature to those seen in this species have been recorded in T. superstes by van Hoepen, and in the related genus of Pseudophyllites in the species garuda by Stoliczka which is included in the species indra by Kossmat. No periodic grooves whatever can be seen on any of my specimens. The body-chamber shows for half a revolution in one specimen, but it is not complete. Suture-line shows that the first lateral lobe is unusually wide. Divisions of saddles and lobes very simple. Second lateral saddle is already on slope of umbilicus. Three auxiliary lobes and saddles. Internal portion of suture-line has a deep antisiphonal lobe and two saddles nearly equal in height, but projections on outer side of second saddle may represent partially suppressed saddles.

This species differs from the widely-distributed T. timotheanus in the entire absence of constrictions, and from this and apparently from all other closely related species in the great width of whorl and the narrowness of umbilicus. It is perhaps nearer to T. superstes van Hoepen than to any other. T. kingianum var. involutior Paulcke is quite close to this species, but has a wider umbilicus.

Several specimens have been obtained from Batley, Bull's Point, Whangaroa, and perhaps Tetragonites sp. juv. Spath (53, p. 300) from Selwyn Rapids is the same species.

Tetragonites simplex n. sp. (Plate 20, figs. 11, 11a; Plate 32, figs. 3, 4.)

Compare—

1845.

Ammonites cala Forbes (1, p. 104, pl. 8, fig. 4).

1865.

Ammonites cala Forbes, in Stol. (11, p. 153, pl. 75, fig. 4).

1895.

Lytoceras (Tetragonites) cala Forbes, in Koss. (28, p. 136, 163, Taf. 17, figs. 12 a-d).

1921.

Tetragonites nuperus van Hoepen (52, p. 13, pl. 3, figs. 3, 4, text-fig. 8).

1922.

Tetragonites nuperus van Hoepen, in Spath (54, p. 119).

Dimensions:—

[The section below cannot be correctly rendered as it contains complex formatting. See the image of the page for a more accurate rendering.]

A. B. C. D. E.
Diameter 19 100 21 100 20 100 80.5 100 37.6 100
Height of last whorl 7 31 7.5 35 8 40 25 31 14 37
Width of last whorl 7.2 37 8 42 8.4 42 29 37 15.4 41
Umbilicus 7.6 40 8 42 7 35 38 47 15.5 41

A, B, C, Tetragonites simplex n. sp., Batley, Kaipara Harbour, N.Z.; D, Tetragonites cala Forbes, in Koss. (28, p. 163); E, Tetragonites nuperus van Hoepen (52, p. 13).

Shell small, discoidal, slightly involute, about one-quarter and therefore with a wide umbilicus. Five whorls in a 10 mm. radius. Whorls rise steeply from umbilicus and curve sharply, almost with an angle, to the evenly-rounded flanks, and pass with another sharp curve or angle to the much-flattened periphery. The section of a whorl is not truly

– 151 –

angular, though the curves are rapid. Surface of shell quite smooth and polished. There are three conspicuous constrictions on the cast in each whorl, but they cannot be distinguished on the shelly matter. They commence on edge of umbilicus and bend sharply forward, becoming much less distinct towards periphery, which they cross with a low forward curve.

Suture-line very simple. Median saddle rounded. External saddle with three simply rounded projections which are less distinct on first lateral saddle and just indicated on second. The five auxiliary saddles are quite simple. First lateral lobe has one simple secondary saddle.

This species is close to Tetragonites nuperus van Hoepen, but the suture-line is a good deal simpler, and in this respect it resembles G. rouvillei de Grossouvre (19, p. 288, pl. 37, fig. 10), though it seems to be quite different from the larger form, fig. 7. It differs from T. cala Forbes in the less angular whorl-section and in the simpler suture-line. Tetragonites kingianum var. involutior is much less inflated, and has a more complex suture-line. In suture-line and in general aspect this species shows a great resemblance to G. bucculentum Pervinquière (Mem. Geol. Soc. de France, 17, Fasc. 2, 3, 1910).

This is not an uncommon species at Bull's Point and Batley; a specimen has also been found at Whangaroa.

Tetragonites margaritatus n. sp. (Plate 20, fig. 5; Plate 30, figs. 5, 6.)

Compare—

1903.

Tetragonites popetensis Yabe (37, p. 48, pl. 7, figs. 4 a, b, 6).

1907.

Lytoceras (Tetragonites) kingianum var. involutior Paulcke (42A, p. 8, pl. 17, figs. 3 a, b, 4 a, b).

Dimensions:—

[The section below cannot be correctly rendered as it contains complex formatting. See the image of the page for a more accurate rendering.]

A. B. C. D. E.
Diameter 15.5 100 12 100 11.5 100 34 100 20.5 100
Height of last whorl 7 45 4.7 39 5 43 14.5 43 9 43
Width of last whorl 8 51 5 42 5.5 49 15 44 9 43
Umbilicus 5 32 4 35 4 36 10.5 30 5.5 26

A, B, Tetragonites margaritatus, Batley, Kaipara Harbour, N.Z.; C, Tetragonites margaritatus, Bull's Point, Kaipara Harbour, N.Z.; D, E, Tetragonites popetensis Yabe (37, p. 48, pl. 7, figs. 3 a, b, 4 a, b).

A very small species, of which there are five examples. Shell is discoid, with an involution of about one-half. Wall of umbilicus steep, but passes quickly into circular curve of flanks and periphery, though the latter is distinctly flattened. Whorls increasing rather rapidly. Umbilicus deep, its slope interrupted by curved surface of whorls, of which there are five in a radius of 8 mm. In one specimen body-chamber is three-quarters of a revolution, but it is not complete. Surface of shell perfectly smooth, and in the type specimen pearly, though a few very indistinct growth-lines can be distinguished. There are occasional deep constrictions which bend strongly forward from bottom of umbilicus until they reach halfway across the flanks, from which point they extend straight to periphery and cross it without change. No more than two can be seen in a revolution. Suture-line with six saddles, well divided considering the small size of the shells. Saddles high and narrow, and there are three auxiliary saddles. On the whole, the suture-line is quite characteristic of the smaller species of Tetragonites.

A number of specimens were found at Batley, and two at Bull's Point.

This species closely resembles T. popetensis, but the umbilicus is rather wider than in that species. The smoothness of the surface of the present

– 152 –

species is another distinction. Umbilicus wider and whorls more projecting than in Paulcke's species T. kingianum var. involutior from South Patagonia.

Pseudophyllites Kossmat, 1895.

Kossmat gives no definite statement of the characteristics of the genus, but from the description of the only species of it that he recognizes the following statement may be taken as embodying the essential features:—

Strong involution, rapid increase especially in the later stages of growth, and very small umbilicus. The whole surface covered with very fine hair-like lines which bend backwards at periphery; there are also broad bands which may be 5 mm. apart, but no constrictions. In the young the suture-lines are phylloid, and the external and first lateral saddles are trifid. Kossmat states that in the larger examples the inner division lobe in the trifid external saddle is the deeper, and the outer division lobe of the first lateral saddle is the deeper. The unsymmetrical nature of the external and first lateral saddles distinguishes Pseudophyllites from Gaudryceras and Tetragonites.

Pseudophyllites indra Forbes. (Plate 20, fig. 1; Plate 29, figs. 3, 4, 5.)

Compare—

  • Ammonites indra Forbes (1, p. 105, pl. 11, fig. 7).

  • Ammonites garuda Forbes (1, p. 102, pl. 7, fig. 1).

  • Ammnoites indra Forbes, in Stol. (11, p. 112, pl. 58, fig. 2).

  • Ammonites garuda Forbes, in Stol. (11, p. 149, pl. 74, fig. 5).

  • Ammonites indra Forbes, in Whiteaves (8, p. 105, pl. 13, fig. 2).

  • Lytoceras (Pseudophyllites) indra Forbes, in Koss. (28, p. 137, pl. 16, figs. 6, 9; pl. 17, figs. 6, 7; pl. 18, fig. 3).

  • Phylloceras indra Forbes, in Whiteaves (27, p. 129).

  • Pseudophyllites indra Forbes, in Whiteaves (34, p. 331).

  • Lytoceras indra Forbes, in Boule and Thevenin (42, p. 44, pl. 1, fig 1).

  • Pseudophyllites indra Forbes, in Woods (40, p. 334, pl. 41, fig. 6).

  • Pseudophyllites indra Forbes, in Kilian and Reboul (46, p. 14).

  • ? Tetragonites teres van Hoepen (51, p. 144, pl. 25, figs. 1, 2).

  • Tetragonites (?) sp. indef. Spath. (59, p. 42, pl. 7, fig. 3).

  • ? Tetragonites virgulatus van Hoepen (52, p. 11, pl. 3, fig. 1, 2; text-fig. 7).

Dimensions:—

[The section below cannot be correctly rendered as it contains complex formatting. See the image of the page for a more accurate rendering.]

A. B. C. D.
Diameter 34 100 28 100 24 100 21 100
Height of last whorl 16 47 14 50 12 50 10 48
Width of last whorl 17.5 51 16 57 13 54 11 52
Umbilicus 8 24 6 21 5.5 23 5 24
E. F. G. H. K.
Diameter 21 100 113 100 20 100 27 100 33 5 100
Height of last whorl 10 48 61 54 9.5 47 12 44 16.7 50
Width of last whorl 12 57 51 45 9 45 12 44 17.1 51
Umbilicus 5 24 18 15 4.8 24 6 22 7.3 22

A, B, Pseudophyllites indra Forbes, Batley, Kaipara Harbour, N.Z.; C, D, E, Pseudophyllites indra Forbes, Bull's Point, Kaipara Harbour, N.Z.; F, G, H, Pseudophyllites indra Forbes, in Kossmat (28, p. 164); K, Tetragonites virgulatus van Hoepen (52, p. 13).

Shell discoidal, but whorls rapidly increasing with an involution of three-quarters. Whorls slightly wider than high in all measured specimens. In this respect the New Zealand specimens differ slightly from the Indian shells that were measured by Kossmat. Umbilical wall steep, and passing into the slightly flattened flank with a broad curve. There is, however, no suggestion of the angle at top of umbilical wall that is characteristic of Tetragonites epigonus Koss. Umbilicus narrow and deep showing four

– 153 –

whorls when diameter is 12 mm. Surface of shell apparently smooth and polished, but when viewed with a lens it is seen to be much striated. The striae start nearly radially at bottom of umbilicus, but curve strongly forward, the curve beginning to decrease at top of umbilical wall, and at top of flank it passes into a faint backward curve precisely as shown by Kossmat (28, Taf. 18, fig. 3). The larger rounded bands to which Kossmat refers are also clearly visible, but they are not prominent, and are somewhat variable in importance. There are no constrictions.

Suture-line is much divided—the median saddle is rather long and has several jags on the side. External saddle unsymmetrically bifid, with the interior portion much smaller than exterior. First lateral saddle also bifid, but exterior portion is here the smaller, and the larger interior portion is divided by a secondary lobe almost as deeply as the main division of saddle, thus giving almost the appearance of a trifid form. Second lateral saddle small, and only three auxiliary saddles can be seen (Kossmat shows four in the Indian examples). External lobe as deep as first lateral, which is very wide and has a prominent secondary saddle in the middle. Auxiliary elements are moderately inclined, and umbilical lobe is not so deep as in most species of Gaudryceras. Internal portion of suture-line can be seen in one of the specimens, but it is a little eroded. Two high saddles not much divided, and the one near umbilical surface is considerably shorter than the other. It is therefore not very different from that of Tetragonites simplex, and of T. epigonum as drawn by Kossmat.

The form and ornamentation are so similar to those of the typical Indian examples which I had the opportunity of examining at the British Museum that I do not feel justified in separating it, notwithstanding the slight but constant differences in dimensions. A single example of P. indra was recorded by Kilian and Reboul in the collection from Seymour Island, and it has also been recorded from South Africa (Pondoland), and from the Nanaimo formation of Vancouver. In India it occurs in the Valudayur and Trigonoarca beds of the highest Senonian. It is considered by de Grossouvre that this species is the same as G. colloti from the Upper Campanian of the south-east of France; but Kossmat points out that, though the ornamentation and apparently the suture-line are closely similar, the dimensions of the European form are different, and he therefore retains this species as distinct. Kossmat also points out that it is closely related to G. postremus Redtenbacher from the Gosau. Spath classes van Hoepen's two species Tetragonites teres and T. virgulatus from Pondoland with this species.

Numerous examples have been found, especially at Bull's Point, also at Batley, and one at Whangaroa. Ferrar has found examples at Te Opu, in the Kaipara Harbour, as well as at Matakohe, on the shores of the harbour six miles north of Bull's Point. A specimen was sent to Professor Kilian, and was identified by him as Pseudophyllites indra.

Pseudophyllites whangaroaensis n. sp. (Plate 20, fig. 2; Plate 21, fig. 11; Plate 32, figs. 5, 6.)

Compare with the species quoted under P. indra Forbes.

Dimensions:—

A.
Diameter 42 100
Height of last whorl 21 50
Width of last whorl 22 53
Umbilicus 11 26

A, Pseudophyllites whangaroaensis n. sp., Whangaroa Harbour, N.Z.

– 154 –

Shell of moderate size, with whorls rapidly increasing in size. Involution almost one-half, with umbilicus narrow and deep. Whorls rise steeply from umbilicus and curve quickly into an inclined but somewhat flattened flank, which in turn leads to a rather flattened periphery. Four whorls at a diameter of 42 mm., but depth of umbilicus makes it almost impossible to expose them. The surface shows fine hair-like ribs, which at the bottom of umbilicus are almost radial; but they bend strongly forward and on flanks become more irregular and discontinuous. They are crossed by a series of low rounded spiral elevations, which are intersected by similar but more irregular radial elevations. These give rise to a check pattern, which is best shown near periphery. With a lens the fine hair-like striae can be seen crossing this checkwork, but they are too fine to show in a photograph. No constrictions can be seen.

The suture-line, which is incompletely shown in the single specimen, is similar to that of P. indra, but is perhaps rather less deeply dissected. The elements of first lateral lobe are somewhat less developed, but the general nature of saddles and lobes is the same.

This species is rendered distinct by its ornamentation, which makes such a striking checkwork pattern on the shell. Kossmat, however, says of Pseudophyllites indra that lightly impressed spiral lines are almost always present, but not so markedly as Stoliczka represents them. I can find no mention of this in Stoliczka. * The statement seems to refer to fine lines rather than the rounded swellings that are so striking in this species. None of the specimens of the species here called Pseudophyllites indra Forbes shows any sign of fine spiral lines or of the sculpture described for this species.

A single specimen has been found at Whangaroa.

Baculites Lamarck.

Straight forms, circular or oval in cross-section, smooth or ornamented.

Baculites rectus n. sp. (Plate 19, fig.]; Plate 32, figs. 9, 10.)

Compare—

1856.

Baculites chicoensis Trask, Proc. Cal. Acad. Nat. Sci., p. 85, p]. 2, fig. 2.

1865.

Baculites chicoensis Gabb (3, pl. 14, fig. 27b; pl. 17, figs. 27, 27a).

1907.

Baculites cf. anceps Paulcke (42A, p. 10, pl. 16, figs. 6, 6a).

1917.

Baculites sp. cf. vagina Forbes, in Woods (57, p. 36, pl. 20, figs. 5 a-d).

The largest fragment measures 135 mm. in length, and the diameters of its cross-section are 30 mm. and 22 mm. at anterior end, and 21 mm. and 17 mm. at posterior end. All except the anterior 38 mm. is septate.

Ornamentation: Surface of shell quite smooth except for some obscure and indefinite growth-lines, and there are no signs of tubercles. Cross-section oval, and the siphuncle is situated at the more pointed end, which is not carinate. Chambers unusually long. First lateral lobe has a prominent projection which makes a distinct bifid division of the lobe. In second lateral lobe are three projections of practically the same size and shape, and the two divisions on either side of median projection are quite similar in development. Saddles deeply bifid. The only species that

[Footnote] * I find this is mentioned under the species Ps. garuda, which Kossmat regards as a synonoym of Ps. indra (11, p. 149, pl. 74, figs. 5, 5a).

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approaches closely to the New Zealand species in characters of suture-line is Baculites chicoensis Trask from California. Baculites ovatus Say from North America, where it extends right through the Fort Pierre beds (Senonian) is also somewhat similar. The smooth surface as well as the suture-line distinguishes this species from all recorded from South Africa.

The species that occurs at Quiriquina, identified as B. vagina by Stein-mann (26 p. 89, Taf. 6, figs. a-e, also text-figs. 8–12), is quite distinct from the New Zealand species both in external sculpture and in the form of the suture-line. The species recorded by Paulcke from South Patagonia (42A, p. 11, pl. 16, figs. 6, 6a) has much more sculpture, and lacks the most distinctive features of the suture-line. Kossmat states that a specimen from India is very similar to an unnamed specimen from California figured by Gabb (3, pl. 17, fig. 27), and names it Baculites vagina var. simplex. It, however, is quite different from the present species.

It thus appears that the present species, B. reclus, is more closely allied to B. chicoensis Trask than to any species of which descriptions are available. This species occurs in Queen Charlotte Sound of British Columbia, as well as in California, where in the type locality it is found only in the, upper division of the Chico, though it has been recorded also in the Lower Chico of San Diego and Silverado (33, p. 27).

Baculites cf. vagina Woods (57, p. 36, pl. 20, fig. 5), which was found at the Amuri Point, in the South Island of New Zealand, almost certainly belongs to this species.

A large number of specimens has been found, though most of them are small fragments. They are most frequent at Bull's Point, though not uncommon at Batley and Whangaroa.

Diplomoceras Hyatt.

The Indian species Diplomoceras rugatum Forbes, to which the following New Zealand species is closely allied, was originally included by Forbes (1, p. 117) in the genus Hamites, but Stoliczka in 1885 used the generic name Amsoceras for this and a large number of related species. Kossmat in 1895 employed the generic title Hamites (Anisoceras). Hyatt in 1900 gave the generic name Diplomoceras to a number of the Upper Cretaceous uncoiled Ammonites, using as the genotype D. cylindraceum Defr. I am unable to obtain a full description of this genotype, but figures are given in Zittel (30A, p. 571, fig. 1187), and the same appear in the next edition, where the Ammonite section is edited by J. P. Smith (47A, p. 654, fig. 1259). The genus Diplomoceras is provisionally adopted for the single New Zealand species, though the suture-line has a very deep external lobe.

Diplomoceras wakanene n. sp. (Plate 19, fig. 3; Plate 31, figs. 8, 9.)

Compare—

  • Diplomoceras indicum Forbes, in Koss. (28, p. 145, Taf. 19, figs. 4 a-c).

  • Diplomoceras subcompressum Forbes, in Koss. (28, p. 145, Taf. 19, figs. 10 a-b, 11 a,b, 12).

  • Diplomoceras rugatum Forbes, in Koss. (28, p. 146, pl. 19, figs 7 a, b, 8 a, b, 9): on the pages quoted full references will be found to the work of Forbes and Stoliczka on these species.

Dimensions: Height of whorl, 11.2 mm.; width, 9 mm.: also, height, 7 mm.; width, 5.5 mm.

– 156 –

Shell nearly elliptical in cross-section; found in widely-curved fragments without any straight portions, which are apparently derived from an irregular spiral shell. Numerous rounded ribs of moderate size extend right round whorl, but they are most prominent on middle of flank and decrease greatly in size as they approach ventral and dorsal surface. No interstitial ribs and no unequal spacing to suggest that constrictions occur. No tubercles. Suture-line generally resembles that of D. rugatum more closely than that of any other Indian species, which are mainly distinguished by the size of second lateral saddles, whose greatest development is in D. rugatum. In the present species second lateral saddles are still larger, and are separated by a lobe as deep as first lateral lobe. External lobe also of much the same depth. First lateral lobe has the peculiarity of showing two prominent projections, of which the internal is the more pronounced. This feature is seen in D. cylindraceum Defr. (47A, fig. 1259; 45, Taf. 45, fig. 47), but not in any of the Indian species, D. indicum D. rugatum, D. subcompressum, as figured by Kossmat (28, Taf, 19). In the present species, however, both the external and the antisiphonal lobes are of unusual width and depth. First lateral lobe has a very similar structure in Zelandites kaiparaensis (Plate 31, fig. 2).

As indicated, this species seems to be closest to D. rugatum Forbes from the Valudayur beds of Pondicherry, but is distinguished by the rounded form of the ribs, absence of constrictions, as well as the form of suture-line. Kossmat states that D. rugatum is very similar to D. cylindraceum Defr. from the highest Senonian of Europe.

A single specimen has been found on the south-west side of Bull's Point, on the Kaipara Harbour, N.Z.

The specific name is that of a well-known Maori chief.

Oxybeloceras Hyatt.

Oxybeloceras sp. (Plate 15.)

Shell nearly straight, with a maximum width of 35 mm., thickness of 16 mm., and length of 292 mm. Surface marked with numerous ribs 4 mm. apart and strongly inclined. On each rib is a small bead-like tubercle on the side of the specimen that is preserved, and there is an indication of another small tubercle near periphery, but the condition of the specimen does not allow this to be seen distinctly. Unfortunately no indication of any suture-line is to be seen, and the only specimen seems to have been a body-chamber only. Costation quite distinct from Aniso-ceras sp. in Woods (57, p. 35, pl. 20, figs. 3, 4). The species of Anisoceras notabile and A. obstrictum figured by Killian and Reboul (46, p. 15, 16) have not inclined costation, and apparently no tubercles.

The present specimen is unfortunately far too imperfect for any specific description. There is a single specimen from the Mangamuka River, Hokianga, in the Auckland Museum. I am indebted to Dr. F. L. Spath for kindly informing me that this species probably belongs to the genus Oxybeloceras of Hyatt. I have not been able to find any statement of the characteristics of this genus, but Spath refers a Pondoland species to it (59, p. 50.)

Ptychoceras d'Orbigny.

Uncoiled forms, for the most part straight, but at intervals bent through 180°

– 157 –

Ptychoceras zelandicum n. sp. (Plate 19, fig. 2; Plate 32, figs. 11, 12.)

Compare—

1845.

Ptychoceras sipho Forbes (1, p. 118, pl. 11, fig. 5).

1865.

Ptychoceras sipho Stol. (11, p. 194, pl. 90, figs. 5–9).

1895.

Ptychoceras sipho Koss. (28, p. 150).

Straight fragments only have been found, but, as the matrix is extremely hard and the specimens fracture easily, it is possible that the species has actually a hooked form, as it usual in this genus. Nearly all the fragments are small, 1–5 mm. in diameter, but there is one piece of a living-chamber 72 mm. in length and 16 mm. in diameter. Cross-section is almost circular, the taper is hardly noticeable, and thus the specimens have a cylindrical appearance. There are deep constrictions at intervals, strongly inclined to the axis. Anterior apex of constriction is at siphuncular side, and in quite small specimens is 4 mm. in advance of posterior portion. Surface of shell quite smooth, or feebly marked with indistinct lines following the general direction of constrictions. Suture-lines simple and symmetrical. Six prominent saddles and six lobes. Siphuncle situated at top of a small saddle in a deep lobe and the antisiphonal line is in a similar deep lobe, which divides the dorsal saddle into two divisions each as large as the other saddles. The six saddles are almost equal in size, and are broader than the lobes. Each saddle is bifid, and the two halves are rounded, and have a slight indentation in each half. The suture on the whole is similar to that of Ptychoceras sipho figured by Forbes (which figure is in the opinion of Kossmat much superior to Stoliczka's). Little distinction can be made between the different saddles in size or form, and the lobes also are almost indistinguishable from one another. The only distinction that can be made is that the external lobe is slightly wider than any of the other, and the median saddle is rather wider than the small saddles at the base of the other lobes.

This species is distinguished from Ptychoceras sipho by its simpler suture-line and by the apparently unhooked form. Ptychoceras sipho has not yet, so far as can be seen in the literature consulted, been compared with any other form. That species occurs in the Valudayur beds of Pondicherry (Upper Senonian).

A large number of fragments of this species has been obtained. It is very frequently found at Whangaroa, and specimens have also been found at Bull's Point and Batley.

Acanthoceras Neumayr.

Kossmat, following Zittel, describes this genus as follows (28, p. 108): “Ribs simple or dichotomously split, straight, thickened in the outer portion; lateral and umbilical tubercles. External portion broad, with a median row of tubercles.“

Group of A. rotomagense: Whorls broad, the ribs usually alternately long and short, with a straight radial arrangement, and seven rows of tubercles—siphonal, umbilical, and two marginal on each side, though either or both of the last may be obliterated. The suture-line has only two large saddles. The bifid external saddle is usually club-shaped. The second lateral saddle is on the umbilical slope and is not much larger than the auxiliaries, of which there are always a few present. The first lateral lobe is usually forked and is about as long as the external lobe. (A summarized translation).

– 158 –

Acanthoceras ultimum n. sp. (Plate 25, figs. 1, 1a; Plate 34, figs. 1, 2.)

Compare—

1894.

Acanthoceras newboldi Koss., typical form (28, p. 5, pl. 12, fgs. 2, 3) = A. rotomagense var. asiatica Jimbo (22, p. 177, Taf. 4, fig. 1).

Dimensions:—

[The section below cannot be correctly rendered as it contains complex formatting. See the image of the page for a more accurate rendering.]

A. B. C. D.
Diameter 94 100 99 100 220 100 149 100
Height of last whorl 37 39 42 42 81 37 60 40
Width of last whorl 40 42 53 53 90 41 80 54
Umbilicus 27 29 32 32 76 35 50 34

A, Acanthoceras ultimum n. sp., Bull's Point, Kaipara Harbour, N.Z.; B, Acanthoceras newboldi var. spinosa Koss. (28, p. 7); C, Acanthoceras newboldi form. typ. Koss. (28, p. 5); D, Acanthoceras rotomagense var. asiatica Jimbo (22, p. 31) = A. newboldi, form. typ. Koss. (28, p. 5).

The table shows that in form this species is quite close to the typical A. newboldi Koss.

Shell of moderate size, discoid, but rather inflated; involution slightly less than one-half. Whorls wider than high. Umbilical wall steep, with widest part of shell just above top, and afterwards the slope towards periphery is gentle until the rounded angle on its edge. Periphery nearly flat. Whorls increasing rapidly in size. Ornamentation striking, but the only specimens are imperfect and fail to display it fully. Four constrictions on last whorl; they are narrow and extend right over periphery without a curve from bottom of umbilicus. Ribs on the two sides of constrictions have small tubercles. Nine tubercles on edge of umbilicus in last whorl. Most of these are large, vertical, and rounded, but a few are almost lamellar, following direction of ribs. Ribs large and conspicuous, rounded when shell is present but sharp and irregular when there is a cast. There are about nineteen on a half-revolution. Some start close to base of a tubercle, but there are also a few interstitial ribs. Half-way between umbilical edge and angle of periphery they rise into a low projection, and at the angle itself they form large projecting sharp tubercles which are much steeper behind than before. On siphuncular line are other lower tubercles which appear to be steeper before than behind. Ribs much flattened between edge of periphery and siphuncle. In the small inner whorls umbilical tubercles alone are present.

Suture-line is relatively simple, and the various arms of the saddles are not deeply intersected. Median saddle only slightly ornamented. Second lateral saddle rather distorted by development of the large umbilical tubercle. Auxiliary saddles are three in number, rapidly decreasing in size, but are not inclined so as to form a deep umbilical lobe. Internal portion of suture-line closely approaches that of A. newboldi, illustrated by Kossmat (28, pl. 3, fig. 2), though the smaller third saddle is less distinct. First lateral lobe indistinctly forked and rather shorter than external lobe. The suture-line generally much more finely divided than that of A. newbold and of the other Indian species figured by Kossmat.

This species is rather more tuberculate than Jimbo's form, which comes from the Ikushumbets. The dimensions show that it comes fairly close to the Indian species.

Only two specimens have been found, one of which is in extremely bad condition. Both of them were found at Bull's Point.

Kossmaticeras (de Grossouvre).

A number of species of ammonites that had been classed in the group Ligati by Stoliczka in 1885 (11) were in 1895 placed in the genus Holcodiscus

– 159 –

by Kossmat (28). However, de Grossouvre pointed out in 1901 that these Upper Cretaceous forms were not cophyletic with the species of Holcodiscus from the Lower Cretaceous, and he then proposed the name Kossmaticeras for them. This name has subsequently been adopted by other authors.

Kilian and Reboul pointed out in 1909 (46) that great differences were displayed in the ornamentation of the species that were referred to the genus Kossmaticeras, and for the groups of these that appeared from their ornamentation to be related he suggested the following subgeneric names: Gunnarites, Madrasites, Grossouvrites, Jacobites, Seymourites, and Grahamites. This subgeneric classification has been adopted by other authors, and has been followed here, though the subgenera are treated as genera. It is also suggested that Madrasites bhavani var. densicostata Kilian and Reboul should be placed in a new genus Maorites, closely allied to the genus Papapuzosia.

Gunnarites Kilian and Reboul, 1909.

Genotype: Gunnarites antarcticus Stuart Weller.

The group of Gunnarites was established by Kilian and Reboul (46, p. 26) in the following words: “Dans le groupe de Kossmaticeras antarcticum Stuart Weller les caractères se modifient par l'apparition de crénelures de plus en plus accentuées sur les côtes, et il finit par en rester, dans l'adulte, une ornamentation qui rapelle vraiment celle de certains Douvilleiceras. Ce sous-groupe, qui contient plusieurs espèces notamment K. kalika Stol., K. antarcticum Stuart Weller, peut-être désigné sous le nom de Gunnarites.” In such descriptions from other countries as are available to me I can find no mention of other species that can be referred to this genus. It is therefore of some interest, and it must be regarded, so far as our present knowledge is concerned, as having its headquarters at Seymour Island. Its representation in New Zealand is, however, considerable, and one species is recorded from India. Possibly there is a species in Madagascar identified by Boule, Thevenin, and Lemoine as K. theobaldianum Stol. Stoliczka did not draw the suture-line of G. kalika, and Kossmat apparently did not see any specimens of that species. Kilian and Reboul (46) merely say of G. antarcticus that the suture-lines are imperfectly preserved, and of G. nordenskjoldi that it closely resembles that of K. karapadense figured by Kossmat (28, p. 41, Taf. 8, fig. 4c). It thus happens that the suturelines in Plate 22 appear to be the first that have been drawn of species of this genus. It is well to make a comparison with those of Madrasites, of which there are abundant drawings by Kossmat, van Hoepen, Spath, and others, and as far as possible with those of other genera originally established by Kilian and Reboul as subgenera of Kossmaticeras. The specimen of G. inflatus from which the suture-line was taken has a whorlheight of 38 mm., that of G. antarcticus is 35 mm., and that of G. zelandicus 24 mm.

The median saddle has a considerable amount of frilling, especially near the top, but generally the suture-line is not finely divided. The external lobe has a strong projection in it which reaches nearly as high as the top of the median saddle. The external saddle is deeply bifid, with three well-developed arms on each side. The exterior half of the saddle is rather larger than the interior half. The first lateral lobe is a little deeper than the external lobe, and it is quite symmetrical. The first lateral saddle is not so deeply divided as the external saddle. The development of the second lateral saddle is much affected by the umbilical tubercle, over and around which its arms pass. In large specimens there may be

– 160 –

six auxiliary saddles, gradually decreasing in size and strongly inclined. The second lateral lobe is not nearly so deep as the external or the first lateral lobe.

The internal portion of the suture-line shows first a large, broad, and much-divided saddle, which is separated by a highly-divided lobe from a second high but narrower saddle, which is succeeded by a deep antisiphonal lobe. It is thus very different from the internal portion of the suture-line of Madrasites theobaldianus Forbes, which is figured by Kossmat (28, pl. 7, fig. 5). This is the only drawing of the internal portion of a suture-line of any Kossmaticeras that I have been able to find. In this drawing there are three well-developed saddles and four auxiliary saddles in the internal suture-line. In general features the whole of the suture-line is not very different from that of Madrasites, though it is somewhat more frilled.

The suture-line of Grossouvrites—taking G. gemmatus as the genotype, as is done by Kilian and Reboul (46, p. 26)—is much more highly divided (46, p. 22, text-fig. 15). It has a great similarity to that of Pachydiscus, as remarked by other authors, and I am inclined to think that it should be placed in that genus. This species has been recorded from New Zealand by Trechmann (56).

One species of Gunnarites has already been recorded from New Zealand under the name Kossmaticeras zelandicum by Marshall (49, p. 444, pl. 33, fig. 2, text-fig. 2).

Gunnarites inflatus Kilian and Reboul. (Plate 22, figs. 1, 1a, 1b; Plate 40, figs. 1, 2.)

Compare—

1909.

Kossmaticeras (Gunnarites) antarcticum var. inflatum Kilian and Reboul (46, p. 33, pl. 10, fg. 1; pl. 11, fg. 1; pl. 16, fg. 1).

Dimensions:—

[The section below cannot be correctly rendered as it contains complex formatting. See the image of the page for a more accurate rendering.]

A. B.
Diameter 130 100 108 100
Height of last whorl 54 45 50 46
Width of last whorl 52 40 46 42
Diameter of umbilicus 38 29 31 29

In the specimen B the succeeding whorls measure H. 20–25, W. 21–25: H. 13, W. 15; H. 7.5, W. 9, respectively. The height is thus seen to increase more rapidly than the width.

A, Gunnarites inflatus, Batley, Kaipara Harbour, N.Z.; B, Gunnarites inflatus, Bull's Point, Kaipara Harbour, N.Z.

The shell is of moderate size, discoid in shape, with a deep umbilicus. Involution nearly one-half. Width of whorls slightly less than height. Wall of umbilicus steep but not perpendicular. A sharp curve at top of umbilical wall. Flanks almost flat and a low curve over periphery. Ornamentation distinct. There are twenty-five strong ribs in a half-revolution. High tubercles situated at top of umbilical wall; they are sharp, slightly twisted, and bent a little backward. From each of the tubercles two ribs arise. An interstitial rib generally arises between each pair of ribs a little distance from umbilical angle. No additional ribs arise higher on flanks. Five constrictions can be distinguished in a revolution. All the ribs are distinctly denticulated. They have a slight backward bend at top of flank, and afterwards bend a little forward at periphery. The first two and a half whorls have tubercles but no ribs.

Suture-line not well preserved so far as the external saddle is concerned, but in general is not highly divided. Median saddle well ornamented at

– 161 –

top, and is rather more than half the height of external saddle. There is a strong process in external lobe. External saddle strongly bifid, and divisions are again nearly symmetrically bifid. First lateral lobe rather deeper than external lobe and quite symmetrical. First lateral saddle large and bifid. Second lateral lobe and second lateral saddle rather irregular because of umbilical tubercles situated there. Auxiliary saddles six in number, rapidly declining backwards, forming a deep umbilical lobe. In internal portion of suture-line is a deep antisiphuncular lobe. Two large much-divided saddles of nearly equal size between it and umbilical angle. These saddles are separated by a deep lobe which has several sharply-pointed processes at base. Outer side of exterior of the two saddles forms with auxiliary saddles a deep umbilical lobe. This internal portion of suture-line differs in a marked manner from that of Madrasites theobaldianus Stol. (28, pp. 36–143, pl. 7, fig. 5). This is the only figurer of the internal portion of a suture-line of Madrasites or Gunnarites that is to be found in accessible literature. This difference alone would justify the separation of Gunnarites from Madrasites, though there is at present no certainty that the same feature occurs in the other species of Gunnarites.

This species was originally placed by Kilian and Reboul as a variety of G. antarcticum Stuart Weller (46, p. 33). Professor Kilian kindly identified a specimen as identical with those obtained from Seymour Island. The specimen is in good condition, and was found by Miss Linley at Batley. It is embedded in a hard sandstone, and part of the suture-line cannot be seen distinctly. Another specimen has since been found at Bull's Point, and fragments probably of this species at Whangaroa. Kilian and Reboul record it from the Snow Hill beds, correlating them with the Trichinopoly beds of India, which they consider the equivalent of the Santonian.

Gunnarites zelandicus Marshall. (Plate 22, fig. 2; Plate 39, figs. 1, 2.)

Compare—

1917.

Kossmaticeras zelandicum Marshall, Trans. N.Z. Inst., vol. 49, p. 444.

This species has already been described and figured (49, p. 444, pl. 33, fig. 2, text-fig. 2), but the figures now given are more complete. The specimen there described was sent to Professor Kilian, and I am much indebted to him for the note that the species is distinct, but very close to G. antarcticum Stuart Weller, so abundant at Seymour Island. The following dimensions were not given in the original description, and must be added:—

Diameter 75 100
Height of last whorl 33 44
Width of last whorl 28 37
Diameter of umbilicus 24 32

The species is distinguished from G. antarcticum Stuart Weller by the following characters: Ribs much more numerous, as many as thirty-six in a half-revolution. The constrictions generally interfere with the development of a single ordinary rib. Ribs more strongly bent forward than in G. antarcticum. Umbilical knots much more numerous. Suture-line generally similar to that of G. inflatum, but the external saddle is rather less symmetrically divided than in that species owing to the greater development of the external portion. The less depth of second lateral lobe is also a more pronounced feature. The nature of the auxiliary lobes unfortunately cannot be seen, nor does any specimen show the internal portion of the suture-line.

No complete specimen has yet been found. The only specimen comes from Batley. The type is in the Otago Museum.

– 162 –

Gunnarites nordenskjoldi Kilian and Reboul. (Plate 21, fig. 8; Plate 36, fig. 6.)

Compare—

1909.

Kossmaticeras antarcticum var. nordenskjoldi (46, p. 33, pl. 12, figs. 4, 5; pl. 14, fig. 2; pl. 15, fig. 3).

Dimensions:—

Diameter 12 100
Height of last whorl 5 42
Width of last whorl 5.5 46
Umbilicus 3.75 31

The specimen measured is the only one in a good state of preservation, and is quite juvenile.

Shell discoid and involute; about one-third of whorl exposed in umbilicus. Whorls almost circular in form. Nine large-tubercles in a revolution on the edge of umbilicus. From each of these three or four ribs take their origin, and usually two interstitial ribs arise between tubercles. All ribs very sharp, but diminish greatly in height towards periphery, and on periphery itself are seen with difficulty. Three constrictions in a revolution are distinct. They commence at the bottom of umbilicus and sweep over flank with a slight forward bend, which is much more pronounced on periphery. They cut off a single rib. Ribs inclined forward, but show no curve until periphery, when there is a strong forward curve. Ribs not denticulate in this young specimen.

Suture-line shows a median saddle about half the length of external saddle, which is relatively slender and not deeply bifid. Both lateral saddles are distinctly bifid, auxiliary saddles small, and the suture-line slopes rapidly backward so as to form a deep umbilical lobe. The external and first lateral lobes are of nearly the same depth, but second lateral lobe much shallower. Both lateral lobes are symmetrically bifid.

Professor Kilian was good enough to identify this specimen for me, and kindly sent me a cast of the Antarctic type for comparison. There appear to me to be some important differences. The ribs in the New Zealand specimen are sharper and are inclined farther forward. The umbilical tubercles also are far less numerous.

A single specimen of this species, found at Batley. Kilian and Reboul compare it to Madrasites karapadensis Koss., and remark that the sutureline is similar to that of M. Karapadensis and M. buddhaicus Koss. Actually, as will be seen from the figures in this paper, there are not many features of distinction between the suture-lines of the various species of Madrasites and Gunnarites—at any rate, in the external portion.

Gunnarites antarcticus Stuart Weller. (Plate 22, fig. 3; Plate 39, figs. 3, 4.)

Compare—

1903.

Holcostephanus antarcticus Stuart Weller (35, vol. 11, p. 4, pl. 2, figs 1, 2).

1909.

Kossmaticeras (Gunnarites) antarcticum Kilian and Reboul (46, p. 31).

Dimensions:—

[The section below cannot be correctly rendered as it contains complex formatting. See the image of the page for a more accurate rendering.]

A. B. C. D.
Diameter 22 100 19 100 65 100 84 100
Height 10 44 8 42 26 40 33 42
Width 9 41 8 42 25 39 31 39
Umbilicus 7 32 6 32 23 35 29 31

A, B, D, Gunnarites antarcticus Stuart Weller, Bull's Point, Kaipara Harbour, N.Z.; C, Gunnarites antarcticus, a cast of No. 135, given to me by Professor Kilian.

– 163 –

This species has already been fully described by Kilian and Reboul (46, p 31), but, as the publication is not easily obtainable in New Zealand, a short description based on the New Zealand specimens is given here.

Shell discoidal, and large when mature. Whorls increasing rather rapidly in size; three whorls in a diameter of 8 mm. Whorls well rounded, but rather higher than wide. Umbilicus of moderate size, with a steep but not vertical wall. Ribs strong; some of them begin a little above bottom of umbilical wall, and at the angle they form twisted knots or tubercles. At this point they bifurcate, and there is usually one interstitial rib between each pair of knots. Every second or third rib is at first strongly inclined forward, but it soon becomes straight. At edge of periphery there is again a slight bend forward, and periphery is passed in a slight forward curve. About twenty-six ribs in a half-revolution, all of them crenulated. Six constrictions in a revolution, bordered in front or behind by a stronger rib, which is toothed like the rest, not smooth as in K. kalika.

No drawing of the suture-line of Gunnarites antarcticum has yet been published. Gunnarites kalika (Stol., 11, p. 140, pl. 70, fig. 5) was represented by a single specimen, which did not show a suture-line; and the many specimens from Seymour Island did not provide Kilian and Reboul with satisfactory material.

The suture-line in general closely resembles that of Madrasites, and we have excellent figures of several species of these by Kossmat (28, p. 39, pl. 7, figs, 1d, 5). The suture-line (Plate 22, fig. 3) is not very complicated; the saddles are distinctly bifid, though external half is rather larger than internal. First lateral lobe not quite symmetrical. First lateral saddle also distinctly bifid and nearly symmetrical, and considerably smaller than external saddle. Unfortunately, the whole of suture-line of this species cannot be seen, and the number of the auxiliary saddles is not known.

Gunnarites antarcticum is clearly related to G. kalika from the Aryalur beds of India, which are not lower than Upper Senonian and perhaps of Campanian age. Kilian and Reboul also compare this species to M. carlottense Whiteaves, from the Senonian of Vancouver (7, pl. 6), but the resemblance to this species does not appear to me to be a close one. Gunnarites kalika differs from this species in having four ribs springing from each umbilical tubercle, while the ribs which border the constrictions are not toothed. Kilian and Reboul make another comparison with Madrasites pachystoma Kossmat (28, p. 39, pl. 7, fig. 1 a-d), but the ribs in that species are not crenulated.

I am very much indebted to Professor Kilian for giving me a cast of Gunnarites antarcticum from Seymour Island, and for being good enough to identify my specimens for me.

Only three specimens have been found, all of which were collected at Bull's Point, but recognizable fragments were found at Batley and Whangaroa.

Madrasites Kilian and Reboul.

This was established by Kilian and Reboul in 1909 as a subgenus of Kossmaticeras, and was characterized by them in the following words (46, p. 25): “Un premier groupe comprend des formes, telles que K. karapadense Kossm. sp., K. bhavani Stol. K. theobaldianum Stol., qui conserve jusque dans l'adulte leur ornamentation caraéristique; nous designerons cette section sous le nom de Madrasites. Certaines formes, comme K. aemilianum Stol., prennent aussi, que l'a justment remarqué M. Kossmat, une ornamentation rappelant celle d'Astieria.”

– 164 –

The New Zealand species that can be referred to Madrasites show no striking differences from these of South India which have been described and figured by Forbes, Stoliczka, and Kossmat. Several of them are clearly seen to be closely allied to Indian species, as will be stated in detail in the specific descriptions. It is interesting to find species that are considered to be closely allied to M. mooraviatoorensis Stol. and M. buddhaicum Kossmat in the same locality. These New Zealand species of Madrasites seem to be quite different from those described from Zululand and Pondoland by Spath (53, 54, 59), by van Hoepen from Pondoland (51, 52), from Japan by Yokoyama (17) and Jimbo (22), and, in my opinion, from those of Vancouver and of California. On the other hand, Madrasites tenuistriatus Paulcke from South Patagonia (36) is closely related to M. sulcatum n. sp., and at Seymour Island Kilian and Reboul recorded M. karapadense (46, p. 30).

Madrasites sulcatus n. sp. (Plate 38, figs. 1, 2.)

Dimensions :—

Diameter 33 100
Height of last whorl 13.5 43
Width of last whorl 12 36
Umbilicus 12 36

Shell discoidal and rather compressed. Whorls distinctly higher than wide. Involution about one-third. Umbilical slope very steep; the surface passes through 80° over a sharp curve. Lower half of flank slopes at first slightly outwards, then is almost flat, but soon slopes gently to periphery, over which it passes in a narrow curve.

There are three deep constrictions in a half-revolution, which always cut off three ribs. Each constriction has a prominent bolster on both sides. Ribs narrow and sharp, with wide interstices. They arise just above umbilical wall and hardly touch tubercles, which are numerous. There are forty-seven ribs in a half-revolution. Some of them begin quite close to an umbilical tubercle, but most of them originate rather higher on the flank and are almost straight. They do not fork, and are not tuberculate. Twelve umbilical tubercles in a half-revolution. Suture-line not sufficiently well shown to allow a satisfactory diagram to be drawn, but it can be seen that it does not differ very much from the other species of Madrasites

This species differs from all other known species of Madrasites. The relatively narrow aperture, close but straight ribs, and numerous tubercles are distinctive.

A single specimen has been found at Bull's Point. It was sent to Professor Kilian for examination, and he kindly sent the following note: “A new variety of Kossmaticeras nordenskjoldi K. & R.“

Madrasites multicostatus n. sp. (Plate 21, fig. 6; Plate 35, figs. 1, 2.)

Compare—

  • Holcodiscus buddhaicus Kossmat (28, p. 42, pl. 8, figs. 3 a, b, c).

  • Holcodiscus karapadensis Kossmat (28, p. 41, pl. 8, figs. 2, 4).

Dimensions:—

[The section below cannot be correctly rendered as it contains complex formatting. See the image of the page for a more accurate rendering.]

A. B. C. D. E.
Diameter 36 100 24.5 100 20 100 36 100 30 100
Height of last whorl 14.5 40 9.5 39 8 40 16 44 10.8 36
Width of last whorl 15.5 44 11 45 9 45 16.5 46 9.2 31
Umbilicus 13.5 37 9 37 8 35 11 31 11.5 38

A, B, C, Madrasites multicostatus from Bull's Point; D, Holcodisens buddhicus Koss; E, Holcodiscus kasapadensis Koss

– 165 –

Shell moderate size with whorls that do not increase rapidly. Involution about one-third. Whorls rather wider than high, with a steep slope from umbilicus, then gradually curving to periphery, which is gently rounded.

Ornamentation: A row of nineteen or twenty tubercles, small and rounded, but varying considerably in size, situated at top of umbilical wall. From these arise a variable number of small rounded ribs, which follow a rather sinuous curve to periphery. At first they are directed slightly forwards, but after passing top of umbilical slope they bend backwards, and on edge of periphery they again bend forward and so continuing pass over periphery. Most of the ribs become quite indistinct in peripheral region. Interstitial ribs occasionally arise at various points. Here and there a number of fine striations can be seen parallel to the ribs. Sometimes striations occur on or between ribs, and sometimes they entirely displace them; in such cases they pass over periphery without interruption. Seven constrictions in last whorl. They arise from bottom of umbilicus and have a thick bolster on either side. They bend forward rather more than ribs, of which they intersect two or three. Constrictions form a conspicuous curve over siphuncle.

Suture-line quite typical of species of Madrasites so far as the main portion of it is concerned, but there is a sudden change of direction after second lateral saddle. The three auxiliary saddles are directed almost radially, and thus a most pronounced umbilical lobe is formed almost like that figured by Kossmat for H. bhavani (28, p. 38, pl. 8, fig. 5). In other respects, however, there is no resemblance between these two species.

Professor Kilian was good enough to examine the type of this species. In a note of a purely preliminary nature he classed it as Kossmaticeras buddhaicum n. var. multicostatum. I consider, however, that it is quite distinct from M. buddhaicum. The present species has a much higher whorl, and more distinct and fewer tubercles. Its ribs do not bifurcate nearly so frequently, and are more numerous—forty-two in place of thirty-one in a half-whorl. The ribs are more rounded and more often vanish on periphery. Suture-line is, of course, quite distinct from that of M. buddhaicum. Ribs in this species are not inclined forward as in M. karapadensis, and aperture is much wider. The constrictions are more numerous, being seven in number, compared with four in the Indian species. M. buddhaicum, which is probably the most closely allied species, is found in the middle horizon of the Trichinopoly group of the Indian occurrences.

Madrasites regularis n. sp. (Plate 21, fig. 7; Plate 35, figs. 3, 4.)

Dimensions:—

[The section below cannot be correctly rendered as it contains complex formatting. See the image of the page for a more accurate rendering.]

A. B.
Diameter 30 100 24 100
Height of last whorl 10.25 34 9 37
Width of last whorl 12 40 10.25 43
Umbilicus 12 40 10 42

A and B, Madrasites regularis, Bull's Point, Kaipara Harbour, N.Z.

These dimensions differ slightly from those of M. multicostatus, immediately preceding.

The most notable features are that the height is small and the umbilicus wide. Shell of moderate size, discoidal. Whorls wider than high. Umbilical wall steep but sloping. Flanks sloping gently to periphery, which is well rounded. Involution about one-half. Whorls not increasing rapidly in height or width.

– 166 –

Ornamentation: Top of umbilical wall crowned with a row of fourteen to seventeen rounded tubercles. These are first noticed on second whorl at a diameter of 7 mm. From each of these tubercles rise two or three moderate rounded ribs, and usually two interstitial ribs begin at the same level in each interval. Ribs much narrower than intervening furrows, but height decreases slightly at periphery, which is crossed with a gentle forward curve. Four large and conspicuous constrictions in a revolution. They begin at bottom of umbilicus and are inclined forward more strongly than ribs, one or two of which they intercept. Constrictions bordered by a large bolster behind and a much smaller one before.

Suture-line in several features is not very different from that of M. multicostatus, but auxiliary saddles are less developed and umbilical lobe is not so conspicuous. Serrations of saddles more finely cut. External lobe wide and process at the bottom more developed. First lateral lobe extremely symmetrical.

This species is distinguished from M. multicostatus by the more regular umbilical tubercles, stronger and more continuous ribs, fewer constrictions, and much less pronounced forward curve of constrictions on periphery. When compared with the Indian species it is found that the shape of the whorl distinguishes it from M. karapadensis Kossm. (28, p. 41, pl. 8, fig. 4). Ribs more continuous, and have not the same strong forward bend at periphery as in the Indian species. Ribs not inclined forward so strongly as in M. bhavani (28, p. 41, pl. 8, fig. 4), which is probably different from Ammonites bhavani Stol. (11, p. 38, pl. 8, fig. 5). They are also less numerous, and the umbilical lobe is less pronounced. M. buddhaicus Koss. (28, p. 42, pl. 8, fig. 3) has less continuous ribs. Of the Indian forms this species resembles M. mooraviatoorensis Stol. most closely (11, p. 158, pl. 77, fig. 4), but the latter species has rather smaller tubercles, while its ribs are closer, the constrictions five to a whorl, and bent more strongly forward. Its suture-line is not dissimilar. This species is placed by Kossmat (28, p. 33) in his first division of Holcodiscus, which he says shows special relationship to the forms of this genus found in the chalk of Europe.

Three specimens have been found at Bull's Point and one at Whangaroa.

Madrasites fortior n. sp. (Plate 21, fig. 12; Plate 41, fig. 3.)

Dimensions:—

A
Diameter 13.5 100
Height of last whorl 5.5 41
Width of last whorl 6.4 47
Umbilicus 4 30

A, Madrasites fortior, Whangaroa Harbour, N.Z.

Shell of moderate size. Whorls nearly circular, increasing rapidly. Whorl rises rapidly from umbilicus and curves evenly into the rounded flank, which in its turn maintains the curve over periphery. Large and prominent smooth ribs, fifteen in a half-revolution, arise from tubercles at top of umbilical wall. Usually two arise from each tubercle, and there are rarely any interstitial ribs. They are inclined slightly forwards, and cross periphery with a slight curve and without any diminution in size. Seven constrictions in a revolution, and they have a stronger inclination than the ribs, but intersect only one of them. The bolster behind each rib is not larger than an ordinary rib. Constrictions cross ribs with a strong forward bow.

– 167 –

Suture-line not well seen; it is apparently of the typical Madrasites form, but less dissected than in the other species.

Only three specimens of this species have been found, two of them very small and immature. There is only one (imperfect) specimen of a mature form. Two come from Whangaroa, the third from Bull's Point.

Madrasites sp. (Plate 41, fig. 4.)

A fragment from Whangaroa in some respects resembles M. cumshewensis. No suture-line could be developed.

Jacobites Kilian and Reboul, 1909.

Kilian and Reboul regarded this group of species as constituting a sub-genus of Kossmaticeras, and gave the following diagnosis of it: “Dans la serie des Kossmaticeras anderssoni K. et R. nous assistons à une importante et rapide modification dès le diametre de 38 mm.; les côtes, fines et flexueuses des tours internes grossissent, s'espacent et finissent par se résoudre en tubercles et épines latérales; des tubercles siphonaux et une caréne apparaissent; ce type est assez analogue a celui que se trouve réalisé dans les Noumayria du Jurassique; cette curieuse section pourra porter le nom Jacobites “(46, p. 26). Up to the present time, unless the form known as Acanthoceras rotalinus Neum. be included, as Kilian and Reboul suggest, the group of Jacobites has not been found outside of Seymour Island. The authors did not give any diagram of the suture-line of Jacobites, but merely state that it was not clearly shown.

Professor Kilian was good enough to examine a few specimens from the present collection, and amongst them he recognized some specimens that were practically identical with J. anderssoni (55, pp. 175, 176). Since then I have obtained many additional specimens from Bull's Point, and one from Whangaroa, while Mr. J. A. Bartrum has given me a cast of a specimen from the entrance of the Wairua River, Hokianga.

The criteria that have been used for placing species in this genus are: The whorls have relatively flat flanks; ribs usually arise from umbilical tubercles and often bifurcate; irregularity in the ribs after a diameter of 60 mm. has been attained; the presence of spines on the flanks and the periphery.

I have obtained specimens of other species which I have no hesitation in placing in this genus, though in the one case the wider spacing of the ribs begins at a diameter of 40 mm. and in the other not before the diameter is 115 mm.

The species here called J. angulare is placed in this genus with some hesitation, because there is no sudden increase in the size of the ribs, though the increase in their development within the limits of a single revolution is considerable. There is a prominent angle on the edge of the periphery which almost has the dimensions of a spine, and there is also a small tubercle on the siphuncular line.

In general the suture-line differs but little from that of Gunnarites; in fact, Spath (54, p. 121) regards the genus Jacobites as a late Campanian development of the sparsicosta group of Kossmaticeras. The first lateral lobe is distinctly wanting in symmetry.

The affinity with M. sparsicostatus and M. denisoni mentioned by Kilian and Reboul does not seem to hold closely in these species.

– 168 –

Holcodiscus sp. described by Woods from Pondoland (46, p. 336, pl. 42, fig. 2) was compared by Kilian and Reboul to J. anderssoni (46, p. 35). Spath points out, however, that this species must be regarded as closely related to Madrasites madrasinus (54, p. 135).

Jacobites anderssoni Kilian and Reboul. (Plate 21, figs. 3, 3a; Plate 37, fig. 4.)

Compare—

1909.

Kossmaticeras (Jacobites) anderssoni Kilian and Reboul (46, p. 35).

Several fragments that were sent to Professor Kilian were identified as belonging to this species.

Dimensions:—

[The section below cannot be correctly rendered as it contains complex formatting. See the image of the page for a more accurate rendering.]

A. B.
Diameter 33 100 54 100
Height of last whorl 13 39 25 46
Width of last whorl 11 33 19 35
Umbilicus 9 27 16 29

A, Jacobites anderssoni K. & R., Bull's Point, Kaipara Harbour, N.Z.; B, Jacobites anderssoni K. & R. (46, p. 35), from measurement of cast kindly sent by Professor W. Kilian, No. 136.

Shell discoidal, with involution about one-half. Whorls higher than wide. Umbilical wall nearly vertical, with a sharply rounded angle to the flanks, which are nearly flat for about two-thirds of their height and then curve in an almost semicircular arc over periphery.

Ornamentation: Large number of tubercles at crest of umbilical wall. Numerous ribs arise from them at about one-third of the distance along the flank, and then pass over periphery with hardly any bend. Three constrictions in a revolution, bordered with a thick bolster before and behind; they are curved forward more sharply than ribs, two of which they intersect. Suture-line well shown. Median saddle slightly frilled. External saddle high and deeply bifid. First lateral saddle much smaller and second situated where tubercles arise at top of umbilical wall. Auxiliary saddles small and suture-line slopes back in umbilical region. External lobe not so deep as first lateral lobe. The latter is trifid but more developed on external side than on internal. Second lateral lobe about as deep as external lobe. Internal portion of suture-line has a deep antisiphuncular lobe and two high saddles separated by a lobe not so deep as the antisiphuncular lobe. Both saddles are bifid. Second saddle the wider, and on its external side are some projections that probably represent additional saddles. This internal portion of the lobe-line more closely resembles that of Gunnarites than that of Madrasites. It suggests an affinity with Acanthoceras.

From this description it will be seen that there is a considerable difference between this form and the mature form of M. anderssom (46, p. 35). The whorl in the New Zealand form is not so high, and the number of umbilical tubercles is a good deal larger. The specimens are immature, and nothing can be said about costation of mature whorls, which is so striking a feature in Kilian and Reboul's specimens from Seymour Island. Kilian and Reboul do not give a figure of the suture-line of the species, but they state that there is a resemblance between this species and K. pondicherrianum Koss. and K. sparsicostatum Koss. (46. p. 36), and they state that the horizon is that of the Valudayur beds.

– 169 –

Jacobites angularis n. sp. (Plate 21, fig. 2; Plate 36, figs. 4, 5.)

Dimensions:—

[The section below cannot be correctly rendered as it contains complex formatting. See the image of the page for a more accurate rendering.]

A. B.
Diameter 55 100 38 100
Height of last whorl 23 42 15 39
Width of last whorl 25 45 17 45
Umbilicus 17 31 12 31

A, B, Jacobites angularis, from Bull's Point, Kaipara Harbour, N.Z.

Shell of small or moderate size. Whorls rather wider than high, with a distinct angle on edge of periphery as well as one much less distinct halfway between edge of periphery and umbilicus. Involution rather less than one-third. Whorls increasing rather rapidly in size.

Ornamentation: A few large ribs arise at bottom of umbilicus, and when they reach top of umbilical slope they develop into prominent elevated tubercles from which arise three and sometimes four ribs. There are also one or two interstitial ribs which commence on edge of umbilical wall between tubercles. Ribs at first bend slightly forward, and this bend is maintained until they reach edge of periphery, where each of them swells into a low rounded tubercle and bends backwards so as to pass over periphery almost at right angles, or with a slight backward curve. Ribs do not decrease in peripheral region, and on siphuncular line swell into small rounded tubercles. None of the ribs are serrated. In young stage the ribs when well preserved are very sharp and are situated quite close together; but when older they become spaced out considerably. Constrictions are not conspicuous, and do not interefere with the regularity of the ribbing.

Suture-line : Median saddle a little frilled and external lobe is not particularly deep. External saddle rather high, narrow, and deeply bifid; its first large external arm is well over top of median saddle. First lateral lobe slightly deeper than external lobe, and, as in the other species of Jacobites, it is not quite regularly trifid, for the external projection at bottom of this lobe is rather larger than internal one. First lateral saddle a good deal smaller than external one, and second lateral is on edge of umbilicus and its development is rather affected by umbilical tubercle. Five auxiliary saddles are small, slope backwards, rapidly diminish, and form a distinct umbilical lobe. This species is distinguished by its relatively wide aperture, strong umbilical tubercles, and the regular rounded tubercles on each of the ribs. In the available literature I cannot find a description of any species that comes close to this one.

Three specimens found at Bull's Point.

Jacobites minimus n. sp. (Plate 21, fig. 5; Plate 38, figs. 3, 4.)

This small shell is probably immature, but the very marked sculpture characterizes it as a different species from any other in this collection.

Dimensions:—

A.
Diameter 8.75 100
Height of last whorl 4.1 47
Width of last whorl 3.75 43
Umbilicus 2 23

A, Jacobites minimus, Bull's Point, Kaipara Harbour, N.Z.

Whorls slightly compressed and strongly involute. Umbilical wall steep but not vertical. Widest part of whorl just above umbilicus, whence there is a gradual slope on flank towards periphery, on the edge of which is a rounded angle. Periphery gently rounded.

– 170 –

Ornamentation; On the edge of umbilicus are seven large tubercles in a whorl, from each of which two ribs arise, and there are two or four interstitial ribs in each interval. Seventeen ribs in a half-revolution. Ribs are rounded and at first bend slightly backward, but at a higher level on flank they take a gentle bend forward, and at edge of periphery there is a strong rounded tubercle on each rib. Across periphery the ribs run straight, and there is another rounded tubercle on median line. Between the tubercles the ribs are less elevated than on flanks. Suture-line shows five saddles, which gradually decrease in size from ventral surface to umilicus. The external and first lateral saddles are symmetrically bifid, and lobes trifid.

Lobes all of much the same depth, and suture-line bends backward to a considerable extent as it approaches umbilicus. On the whole, the suture-line has a close resemblance to that of a young specimen of Gunnarites (Plate 22, fig. 1b), but it is a good deal simpler, and more even

In the available literature I am unable to find any species that resembles this one closely. It is perhaps closer to A. idoneus Stol. than to any other, but differs from it in having umbilical tubercles and in the symmetrical development of the two sides.

The single specimen from Batley is probably immature, but is in such a good state of preservation and so distinct that it has been described as a new species.

Jacobites whangaroaensis n. sp. (Plate 21, fig. 1; Plate 37, fig. 1.)

Dimensions:—

147 100
Height of last whorl 63 43
Width of last whorl 56 38
Umbilicus 46 31

Involution about two-fifths. Whorls higher than wide. Umbilical wall steep but not vertical, rounded at angle. Whorl broadest at about one-third of its height above umbilical angle; thence it slopes gently to periphery, which is broad and well rounded.

Ornamentation: About ten large tubercles on edge of umbilicus; they are larger radially than longitudinally. Four ribs rise from each tubercle, and there is usually one interstitial rib between each pair of tubercles. Ribs close together and rounded on inner whorls, and more widely spaced on body-whorl, where at margin of periphery many of the ribs bifurcate and become extremely sharp and high and apparently spiny.

Suture-line only partially visible. Median saddle a little dissected on margin. External saddle high and deeply bifid, external half being slightly larger than internal half. First lateral lobe deeper than external lobe, and unequally trifid, for the external of the two major projections is rather larger than the internal one.

The species differs from J. anderssoni Kilian and Reboul in the sharpness of the ribs in the body-whorl and their regularity. They are also more closely spaced. There is no peripheral angle as in J. angularis n. sp.

A single specimen, found at Whangaroa.

Jacobites waitapuensis n. sp. (Plate 23, fig. 2; Plate 44, fig. 1; Plate 45, fig. 2.)

Dimensions—

Diameter 100
Height of last whorl 40
Width of last whorl 31
Umbilicus 33
– 171 –

Aperture widely oval. Umbilical wall steep, with a rounded angle to the flank, which is moderately flat, though it has its. widest part rather nearer umbilicus than middle of flank, which slopes uniformly and gently to the well-rounded periphery.

Ornamentation: Five constrictions in a whorl, each with a prominent bolster before and behind. They are first inclined slightly forward, but in middle of flank they become almost truly radial, soon taking a stronger bend forward and passing over periphery with a distinct forward loop. At top of umbilical wall there are prominent rather rounded tubercles, eighteen in a whorl. From each of these arise three or four ribs, though some of these arise from bottom of umbilicus. Ribs at first bend slightly forward but soon straighten up and pass straight across periphery. Each constriction cuts off three ribs on each side. There are in addition low rounded tubercles on margin of periphery, twenty-three in a revolution, but unfortunately these can hardly be seen in the photograph. Indistinct tubercles also occur on periphery.

Sature-line: Median saddle frilled to a considerable extent, much more than in the two previous species. External saddle deeply bifid, and the two portions are about as unequal as in other species of this genus. First lateral saddle relatively rather larger than in the three previous species. The development of second lateral saddle is affected by umbilical tubercles. Auxiliary saddles, as in the other species, are strongly inclined, forming a deep umbilical lobe. The internal suture-line, which, however, is not figured, is close to that of J. angulare in form.

I am unable to find any described species that approaches closely to this one. The tuberculate periphery and median line, as well as the suture-line, distinguish it at once from all species of Kossmaticeras. The same features, as well as the more rounded form and coarser ribs, enable it to be distinguished at once from Maorites. It certainly comes nearer to Parapachydiscus than the other species of the genus. The whorl, however, is rather narrow, the ornamentation is distinctive, and the first lateral saddle shows lack of symmetry.

A single specimen, in good condition, from Nedler's, at Whangaroa.

Neomadrasites.

Tuberciles on shoulder and on median line. Suture-line resembles that of Madrasites.

Neomadrasites nodulosus n. sp. (Plate 21, figs. 4, 4a; Plate 36, figs. 1–3.)

Dimensions:

[The section below cannot be correctly rendered as it contains complex formatting. See the image of the page for a more accurate rendering.]

A. B.
Diameter 29 100 20 100
Height of last whorl 11 35 7.5 37
Width of last whorl 13 45 9.25 46
Umbilicus 13 45 9 45

A, B, Neomadrasites nodulosus. from Bull's Point, Kaipara Harbour, N.Z.

Shell small, discoid. When the diameter is 29 mm. there are three whorls. Whorls decidedly wider than high, and increasing in width rather rapidly. Involution about one-half. Umbilical wall steep but rounding off into flanks that are gently inclined towards periphery, at edge of which there is a distinct angle, and periphery itself is gently rounded.

Ornamentation: At top of umbilical slope are a number of rounded tubercles, as many as seven in a half-revolution. Three or four sharp

– 172 –

but smooth ribs start from each tubercle, and there are two or three interstitial ribs between each pair of tubercles. Altogether forty ribs in a half-revolution. At edge of periphery ribs unite together in twos or threes into rounded tubercles situated irregularly with respect to umbilical tubercles, and here are also one or two interstitial ribs which do not touch tubercles. Ribs almost straight to edge of periphery, when they bend strongly forward and across it with a pronounced forward curve. At median line each rib has a small rounded projection or tubercle. On inner whorls the umbilical tubercles are well marked but the others are indistinct. In a half-revolution there are two constrictions with a prominent bolster on each side. These have the median projection, and they may join in the tubercles at edge of periphery.

Suture-line shows no striking features as compared with other related species of Kossmaticeratidae. Median saddle nearly simple, and external lobe not important. External saddle high and symmetrically bifid, as are lateral saddles, which rapidly decrease in size. First lateral lobe symmetrically trifid. At edge of umbilical wall suture-line bends sharply backwards and auxiliaries are directed almost internally. A similar sudden declension of suture-line is noticeable in Madrasites multicostatus (Plate 21, fig. 6) and in Brahmaites brahma (28, pl. 8, fig. 9). The internal portion of suture-line shows five saddles, which is quite distinct from that of Madrasites (28, pL. 7, fig. 5), and from that of Jacobites anderssoni (Plate 21, fig. 3a) as well as from Gunnarites.

A specimen sent to Professor Kilian was characterized by him as follows: “II convient de signaler en outre une forme trés curieuse, que je rattache à Jacobites, et dont M. Marshall m'a soumis un fragment, qui présente une modification progressive de l'ornamentation (apparition outre la présence des tubercles ombilicaux, de tubercles réunissant deux côtés du côté externe des flancs, et en outre, indication d'une série des tubercles siphonaux moins accentués, mais trés nets).” (55, p. 176.)

I have not adopted Professor Kilian's suggestion, because the development and drawing of the suture-line appears to me to indicate a closer relationship to Madrasites than to Jacobites. In its details, however, the ornamentation is distinct from both. I therefore suggest a new genus, Neomadrasites.

Several specimens, but none quite complete, have been found at Bull's Point.

Brahmaites Kossmat.

In the original diagnosis of this genus Kossmat says (28, p. 45) that it is very closely related to Holcodiscus (= Kossmaticeras Grossouvre). The most characteristic features are the presence of siphonal knots placed on ribs, the prominent bolsters bordering constrictions, and the highly variable nature of sculpture. In three specimens of middle age the flanks only are sculptured. At a later stage the ribs develop into high ridges which leap over periphery in a manner that is quite different from that of Holcodiscus.

The present species, B. rotundus, has the young form only, but the largest specimen shows a tendency towards the development of tubercles on the shoulder—a fact that definitely distinguishes it from B. brahma and the two other species B. vishnu and B. haugi.

So far as records go, the genus appears to be restricted to India. Some of the New Zealand specimens were sent to Professor Kilian, who was good enough to inform me that he agreed that they belonged to a new species of Brahmaites (55, p. 175).

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Brahmaites rotundus n. sp. (Plate 21, fig. 9; Plate 31, figs. 4, 5.)

Dimensions:—

[The section below cannot be correctly rendered as it contains complex formatting. See the image of the page for a more accurate rendering.]

A B. C. D. E.
Diameter 19.75 100 16 100 12 100 11 100 88 100
Height of last whorl 7 35 5 31 4 33 3.8 36 25 28
Width of last whorl 8.75 44 7.50 46 7 58 6.5 60 38 43
Umbilicus 7 35 5.75 36 4.75 39 4 39 42 48

A, B, C, D, Brahmaites rotundus, all from Bull's Point, Kaipara Harbour, N.Z.: E, Brahmaites brahma Forbes, in Koss. (28, p. 45).

The whorl is clearly much wider and the umbilicus narrower than in Brahmaites brahma.

Shell small, whorls much wider than high, especially in the younger specimens. Involution about one-quarter, and umbilicus deep. Wall of umbilicus steep but not vertical. Flank sharply rounded; periphery wide, with gentle curve.

Ornamentation: About eleven rounded tubercles in a revolution, situated on edge of flank near but not on edge of umbilicus. Usually three ribs start from each knob, and there are other interstitial ribs which start on side of umbilical wall. Ribs rather sharp, and separated by considerable intervals. At first they bend a little forward; the curve is soon increased, and near periphery it is strong, though the ribs themselves become less distinct. They cross periphery with a strong bow forward. Two or three deep constrictions in a revolution, bordered behind by a thick bolster. They have exactly the same forward inclination as the ribs, with which they do not interfere. Occasionally there is a slight suggestion of the presence of tubercles on edge of periphery, as in Neomadrasites nodulosus, but the ribs are not affected, and there is no indication of median tubercles on periphery, except that the bolster behind each constriction is swollen on the median line, as is also the case in B. brahma.

Suture-line was drawn from a very small specimen, but it is clear in all the specimens that the first lateral lobe is unsymmetrical. The irregular trilobed nature is due to the larger development of external than internal projection in this lobe. Suture-line does not show such a sudden backward curve in the region of auxiliary saddles as is seen in so many of the related species of Madrasites. This asymmetry of the first lateral lobe is not, however, noticeable in B. brahma. Internal portion of suture-line is more like that of B. brahma (28, pl. 8, fig. 9).

This species is not very different from B. brahma (28, p. 45, figs. 7—9), especially in the form of aperture and in ornamentation, though ribs are rather closer together. Its form is rather more rounded and suture-line is less divided.

Several specimens have been obtained from Batley and Bull's Point, but none at Whangaroa. This species is commonest at the first locality.

Maorites n. gen.

Genotype: Maorites tenuicostatus Marshall.

This genus is suggested for species that have the general form of Puzosia or Parapuzosia but possess umbilical tubercles—at any rate, in the young form. The suture-line is typically of the Puzosid type, though usually more highly developed than in the known genera of that group.

The general form has a highly involute whorl with flat flanks, the widest part of which is just above the steep umbilical slope. Ornamented with a number of ribs, usually quite fine. These at first are directed forward,

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but on the flanks they become radial and cross periphery at right angles. About five constrictions more or less decidedly marked in a revolution. Many of the ribs arise from well-marked tubercles on edge of umbilicus, but there are always several interstitial ribs as well.

Suture-line: Median saddle a good deal frilled, and external lobe wide and deep. First lateral lobe has a highly important development. It is a good deal deeper than external lobe, and also is very wide. It is unsymmetrically bifid owing to the unequal development of the elements in lobe, those on external side being much larger and stronger than those on internal side. Second lateral lobe also unsymmetrical. Five or six auxiliary lobes are present and strongly inclined outwards. External saddle bifid, but with a much stronger development on external than on internal side. First lateral saddle also bifid, and in this case internal portion of saddle is a good deal larger than external. Second lateral saddle much smaller, and sometimes a little distorted by the tubercles, for it is situated on edge of umbilicus. Five or six auxiliary saddles quite small, and strongly inclined.

It is noticeable that Stoliczka placed his species Ammonites madrasinus, A. Kandi, A. aemilianus, A. bhavam, and A. kaloka in close proximity to Ammonites bhima, A. planulatus, &c., as though he thought that there were affinities between them. The last two of these species were afterwards classed by Kossmat in the genus Puzosia. On the other hand, Ammonites pacificus, A. papillatus, A. mooraviatoorensis were by Stoliczka far removed from those first named, though both groups were placed in the large and comprehensive class of Ligati (11, App. 6, 7). Kossmat, on the other hand, subsequently placed both of these groups (A. madrasinus and A. pacificus) in the genus Holcodiscus, but, of course, excluded A. bhima and A. planulatus. It seems, however that Kossmat did not have the opportunity of examining any of Stoliczka's specimens of the first group, but he saw one specimen of A. aemilianus in the museum at Vienna. Kossmat also had ten specimens that he ascribed to Stoliczka's species A. bhavani in the Warth collection, which was the one that provided most of the specimens that he studied. It is also noticeable that Stoliczka's drawings of the suture-lines of the species in the A. madrasinus group, though always somewhat sketchy, are in some respects distinctly different from those in the second, or A. pacificus, group, now mainly classed by Kilian and Reboul as Madrasites. (Compare 11, pl. 69, fig. 7, and pl. 70, figs. 3, 8, with pl. 77, figs. 5, 8, 9b, &c.). The suture-lines in the former are more divided, and they have dissymmetry in the first lateral lobe. In addition, the first lateral lobe is very deep. In the second, or A. pacificus, group, on the other hand, the suture-line is far less finely divided; there is almost complete symmetry in the first lateral lobe, which is relatively less important and either not deeper or very little deeper than the ventral lobe. The descent to the umbilical lobe is also far less regular in this second group. The shells of the first group also in most cases show a definite tuberculate character in the umbilical region, which is generally absent in the second group—that is, the ribs more decidedly and definitely arise from somewhat lamellar tubercles, which may be absent in the adult stage. The tubercles in the second group are much more rounded in their form.

The genus Maorites agrees with the species of the first group in the majority of their characters, and it is here suggested that the species Ammonites kandi, A. aemilianus, and A. madrasinus of Stoliczka should be placed in this genus, though this point cannot be definitely settled until

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the types of the Indian species which were described by Stoliczka are re-examined and their suture-lines have been carefully drawn.

In regard to Ammonites bhavani there is considerable difficulty. It is a form without any striking specific characters in its ornamentation; and in the absence of well-drawn suture-lines of Stoliczka's specimens it is hard to be certain whether a species in another collection is correctly identified with it. If Kossmat's specimens do belong to the true A. bhavani of Stoliczka there is no doubt that the species is correctly placed in the second group referred to above (the A. pacificus group). This has been done by Kossmat, and Kilian and Reboul have subsequently placed it in their subgenus Madrasites. On the other hand, Stoliczka's classification leads to the idea that his A. bhavani should be placed in the first of the two groups—that is, the group of Ammonites madrasinus. In order to make this point clear, a table is given in which the relative dimensions of Stoliczka's specimens of Madrasites bhavani are given as well as those of Kossmat, and also two of Kilian and Reboul's specimens of Kossmaticeras (Madrasites) bhavani var. densicostata, the last measurements being obtained from the casts that were kindly forwarded to me by Professor Kilian.

[The section below cannot be correctly rendered as it contains complex formatting. See the image of the page for a more accurate rendering.]

A. B. C. D. E. F.
Diameter 38 100 65 100 36 100 66 100 63 100 125 100
Height of last whorl 37 41 15 42 26 40 30 47 51 40
Width of last whorl 32 31 14.5 40 24 36 18 29 31 25
Umbilicus 24 26 11 30 22 33 13 21 31 25

A, B, Ammonites bhavam Stol. (11, p. 138); C, D, Holcodisens bhavani Koss. (28, p. 145); E, F, Kossmaticeras (Madrasites) bhavani var. densicostatum Kilian and Reboul (46, pl. 15, fig. 4; pl. 18, fig. 1).

These dimensions show that Kossmat's specimens are distinctly wider than the original ones of Stoliczka, and have a wider umbilicus, while Kilian and Reboul's specimens have a slightly narrower whorl.

Ammonites kalika appears to me to belong to a different group. It is the only Indian species of this nature that shows denticulations on the ribs; and it should almost certainly be classed with the species of Gunnarites described in the present collection. Stoliczka gives no drawing of the suture-line of this species, and Kossmat apparently saw no specimen of it. Those obtained in the present collection show that the species of Gunnarites are closely related to Madrasites, though the internal portion of the suture-line shows important differences if Kossmat's drawing of M. theobaldianus is taken as type. The New Zealand species M. regularis, however, shows a similarity to Gunnarites. The large and important collection of Antarctic species from Seymour Island described by Kilian and Reboul were in too bad a condition to allow the suture-lines to be traced.

The affinities of Maorites and its genealogy are a little hard to decide. As stated more fully subsequently, the author, in spite of the great weight of authority in favour of regarding Puzosia and Parapuzosia as derived from the Desmoceratidae, is himself of opinion that they are an independent branch derived from a Hoplitid ancestry. In connection with this it is important to recall the words of Sarasin, who wrote as follows (29A, p. 799): “Puzosia est du reste derivée directement de Desmoceras … Quant a l'origine de Desmoceras … il se rapproche nettement de Hoplites et il est a mon avis incontestablement derivée de Hoplites ou tout au moins de Perisphinctes.”

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Djanélidze in 1922 established Dalmasiceras, a new subgenus of Hoplites, from the Upper Tithonian of France (60, p. 256). The species of Dalmasiceras described by him differ so much in appearance and ornamentation from the typical Hoplites that doubt might well be entertained as to the real position of the genus. However, Djanélidze says, “Remarquons d'abord que Dalmasiceras est sans conteste une branche specialisée de Hoplites.” The forms of Maorites and of Puzosia are extremely similar to that of Dalmasiceras, and the same is equally true of the general features of the suture-line of these genera, both in its external and internal portions. There is, however, a difference in sculpture. Apart from the tuberculate nature of the ornamentation of the typical Hoplites, which is not developed to any extent in these genera, there is the marked break of the costation at the periphery. This feature, however, is not constant even in Hoplites itself, for Hyatt remarks that in the young forms the costation is sometimes continuous across the periphery (47A, p. 668). In addition, it is noticeable that Sonneratia, a genus included by Hyatt in the Hoplitidae, has continuous ribs across the periphery, and it therefore seems that this feature of ornamentation should not be emphasized too much. Maorites appears to be closer to the Hoplitid stock through Dalmasiceras than does Puzosia. In the suture-line the great depth and width of the external lobe, the depth of the first lateral lobe, and its asymmetry are more strongly marked than in Puzosia, and make a close approach to the conditions of the suture-line of Dalmasiceras, though they are more marked than in that genus. Tuberculation on the edge of the umbilicus also is present in Maorites, though absent in Puzosia. It is, however, to be noted that both Jacob and Nowak ascribe asymmetry to the flattening of the flank. This does not appear to hold in the New Zealand species; for, e.g., M. tenuicostatus, which is relatively rounded, has far more marked asymmetry than Puzosia angusta which has an extremely narrow form.

The first specimen of this genus that was found was classed by me under the name Kossmaticeras tenuicostatum (49, p. 445). This specimen was afterwards taken to Europe, and Professor Kilian was good enough to examine it. He classed it with his Madrasites densicostata from Seymour Island (55, p. 175). When the suture-line was developed and drawn, it at once became clear that the specimen could not belong to either Kossmaticeras or Madrasites, and that, on the other hand, it possessed close affinities with Puzosia. Professor Kilian, with the greatest kindness, sent me a cast of two specimens of his Madrasites bhavani var. densicostata, and inspection of these showed that in all probability this species belonged to the same genus as the New Zealand species. The condition of the Seymour Island specimens was, however, so bad that Professor Kilian was not able to develop the suture-lines. I have already stated that in my opinion some of the Indian species described first by Stoliczka, and afterwards placed by Kossmat in the genus Holcodiscus, and later in Kossmaticeras (Madrasites) by Kilian and Reboul, especially K. madrasinum, K. kandi, and K. aemilianum, may also possibly belong to this genus.

The characters of the genus Maorites may be summarized as follows: Form somewhat compressed and resembling that of Puzosia. Ornamentation shows umbilical tubercles a little extended radially. Ribs generally rather fine and sinuous, but continuous across periphery, which they cross without a forward bend. Constrictions deep and with a strong forward inclination. Suture-line in general resembles that of Puzosia, but the first lateral lobe is a little deeper and the external lobe is wide. The unsymmetrical development of the first lateral lobe is marked. The suture-line is greatly dissected.

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Maorites tenuicostatus Marshall. (Plate 23, figs. 1, 1a; Plate 42, figs. 1, 2; Plate 45, fig. 1.)

Compare:—

1917.

Kossmaticeras tenuicostatum Marshall (49, p. 445, pl. 33, fig. 1).

Dimensions :—

[The section below cannot be correctly rendered as it contains complex formatting. See the image of the page for a more accurate rendering.]

A. B. C. D.
Diameter 142 100 143 100 20 100 63 100
Height of last whorl 60 42 60 42 9 45 30 47
Width of last whorl 43 30 43.5 31 7 35 18 29
Umbilicus 35 24 35 24 5 25 13 21

A, B, C, Maorites tenuicostatus Marshall, Batley, Kaipara Harbour, N.Z.; D, Kossmaticeras bhavani var. densicostatum K. & R. (measurements from a cast).

Shell large, discoid. Involution rather more than one-half. A steep rounded slope, nearly vertical in young forms, rises from umbilicus, and greatest width of whorl is attained just above umbilical slope. Flanks nearly flat but with a gently increasing slope towards periphery. Edge of periphery well rounded, and a well-rounded curve over periphery.

Ornamentation: In mature form constrictions not distinct, and in no way interfere with costation, for they have the same slope as ribs. A large number of narrow rounded ribs, which in mature form are almost constant in size, from bottom of umbilicus to periphery. In younger forms ribs do not all extend to bottom of umbilicus, and on its margin about every fifth rib is swollen and almost forms a small tubercle extended in a radial direction. In the youngest forms there are no ribs or tubercules and the whorl is much wider. Some interstitial ribs arise on lower part of flank, but very few above a third of distance from umbilicus. With a radius of 70 mm. there are thirteen on a 10 mm. arc of periphery; at 55 mm. fifteen ribs; at 23 mm. twenty ribs; at 12 mm. twenty-eight ribs. The ribs bend slightly backward at top of umbilical edge; thence to the middle of flank there is a forward inclination, but from that point the ribs pass straight over periphery without any curve.

Suture-line is highly dissected. Median saddle much ornamented. External saddle deeply bifid, but external half much larger than internal half. First lateral saddle also deeply bifid, but internal portion much smaller than external portion. Second lateral saddle small. Six auxiliary saddles. External lobe wide with several frilled projections. First lateral lobe very deep and noticeably wanting in symmetry, for the projections and forks are much more developed on external than on internal side. Second lateral lobe much shallower, but still wanting in symmetry. Auxiliary lobes small and unimportant, but with the saddles form a deep umbilical lobe. Antisiphonal lobe also deep and again wanting in symmetry. The saddle next to it is very high, but the four others rapidly decrease in height, and the lobes are small, and thus the internal side of umbilical lobe is extremely steep. Both internal and external portions of suture-line have a remarkable resemblance to Dalmasiceras, and a rather less marked one to Puzosia.

A specimen of this species was sent to Professor Kilian, who kindly examined it, and returned it with a note: “Kossmaticeras (Madrasites) n. sp., possibly the mature form of M. bhavani var. densicostatus.” I consider, however, that it is to be distinguished from that species by the fineness of the costation, the gradual slope into the umbilicus, the indistinct constrictions, the small size of the umbilical tubercles.

Two adult specimens and several smaller ones from Batley and Bull's Point, and a small one from Whangaroa. The type is in the Otago Museum.

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Maorites densicostatus Kilian and Reboul. (Plate 24, fig. 1; Plate 44, fig. 2; Plate 45, fig. 4.)

Compare the species mentioned below under Maorites suturalis n. sp.

Dimensions of species of Ammonites apparently related to Maorites

densicostatus :—

[The section below cannot be correctly rendered as it contains complex formatting. See the image of the page for a more accurate rendering.]

A. B. C. D. E. F. G.
Diameter 49 100 55 100 60 100 93 100 63 100 125 100 142 100
Height of whorl 23 47 40 50 42 30 47 51 40 60 42
Width of whorl 12 24 34 36 21 18 29 31 25 43 30
Umbilicus 12 24 33 16 29 13 21 31 25 35 24
H. J. K. L. M. N.
Diameter 100 74 100 36 100 66 100 38 100 65 100
Height of whorl 40 35 47 15 42 26 40 37 41
Width of whorl 31 22 30 14.5 40 24 36 32 31
Umbilicus 33 18 24 11 30 22 33 24 26

A, Maorites densicostatus K. & R., Bull's Point, Kaipara Harbour, N.Z.; B, Ammonites kandi Stol. (11, pl. 70, fig. 4); C, Ammonites aemilianus Stol. (11, pl. 70, fig. 7); D, Ammonites mudiasinus Stol. (11, pl. 70, fig. 1); E, Kossmaticeras (Madrasites) bhavni var. densicostatum Kilian and Reboul (46, pl. 15) (measured from a cast kindly presented by Professor Kilian); F, Kossmaticeras (Madiasites) bhavani var. densi-costatum K. & R. (46, pl. 18, fig. 1): G, Kossmaticeras tenuicostatum Marshall (49, pl. 33, fig. 1); H, Jacobites waitapuensis n. sp., Whangaroa, N.Z.; J, Maorites, suturalis n. sp. Batley, Kaipara Harbour, N.Z.: K, L, Kossimaticeras bhavani Kossmat (28. p. 145); M, N, Ammonites bhavani Stol. (11, p. 138).

The table shows clearly how very similar the dimensions of this species are to those of Kilian and Reboul's form Kossmaticeras (Madrasites) bhavani var. densicostatum; but the suture-line of that species is said by the authors to be quite similar to the suture-line drawn by Kossmat of the form that he identified with K. bhavani Stol., and in that case it must be radically different from the suture-line of this species, which, as will be seen on Plate 24, fig. 1, is quite Puzosid in form. From inspection of the cast of his species that Professor Kilian was good enough to send me, however, it seems to me that the suture-line if developed would be similar to that of this species.

Ornamentation: There are numerous fine sharp ribs narrower than the intervening furrows, and narrower and sharper than in the closely allied species Maorites suturalis. Ribs at first bent forwards, but at about one-third of the flank they bend backwards and, becoming strictly radial, cross periphery without interruption and without any bend. Most of ribs start from tubercles at top of umbilical wall, but there are several interstitial ribs as well. A few deep constrictions, most noticable in last whorl. They have a moderate bolster-rib before and behind, and as they have a strong forward inclination they intersect several of the ribs, many of which fork close to posterior bolster. Constrictions cross periphery with a pronounced forward curve. Umbilical tubercles are numerous and are elongated radially.

Suture-line much less complex than that of M. tenuicostata and M. suturalis. Median saddle not so much divided. External saddle deeply bifid, but, as usual, exterior portion is a good deal larger than interior. First lateral saddle unsymmetrically bifid. Second lateral quite small. and auxiliaries rapidly diminish in size and are steeply inclined. External lobe wide, but not nearly as deep as first lateral lobe, which has the usual want of symmetry, is wide and deep, and extends over almost half of length of suture-line. Second lateral lobe much smaller, and auxiliaries small and unimportant. The inclination of these elements causes suture-line to form a deep umbilical lobe. It is noticeable that, as is also the case in the other species of Maorites, the external saddle is exactly the same

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width as the first lateral lobe; while in Puzosia it is about three-quarters of the width, and in Desmoceras the two are about equal. The external lobe in this genus is of greater importance than in other genera, and this makes the external saddle appear much more upright than in Puzosia.

One specimen only has been found, and it comes from Batley. The Indian species to which it is closely allied come from the Aryalur group, except K. bhaiani Stol. This comes from the Trichinopoly group, which is classed in the Lower Senonian, while the former are placed in the Upper Senonian. The New Zealand species has a rather broader and more rounded periphery than the Seymour Island specimen which it so closely resembles.

Maorites suturalis n. sp. (Plate 23, fig. 3; Plate 43, fig. 1; Plate 45, fig. 5.)

Compare—

  • Ammonites kandi (11, p. 140, pl. 70, fig. 4).

  • Ammonites aemilianus (11, p. 141, pl. 70, fig. 7).

  • Ammonites madrasinus (11, p. 139, pl. 70, fig. 1).

  • Kossmaticeras (Madrasites) bhavani var. densicostatum (46, p. 30, pl. 18, fig. 1; pl. 15, fig. 4).

Dimensions :—

[The section below cannot be correctly rendered as it contains complex formatting. See the image of the page for a more accurate rendering.]

A. B. C. D. E.
Diameter 74 100 55 100 60 100 92 100 63 100
Height of last whorl 35 47 40 50 42 30 47
Width of last whorl 22 30 34 36 21 18 29
Umbilicus 18 24 33 16 29 13 21

A, Maorites suturalis, type, Batley, Kaipara Harbour, N.Z.; B, Ammonites kandi (11, p. 140, pl. 70, fig. 4); C, Ammonites aemilianus (11, pl. 70, fig. 7); D, Ammonites madrasinus (11, pl. 70, fig. 1); E, Kossmaticeras (Madrasites) bhavani var. densicostatum (46, pl. 15, fig. 4).

It is evident that the dimensions of this species are very like those of Kilian and Reboul's species from Seymour Island.

Shell of moderate size, strongly involute (about two-fifths) and a good deal compressed. Umbilicus has a nearly vertical wall, and at the top of it the whorl has its greatest thickness. The sides are almost flat and the periphery is well rounded.

Ornamentation: Well-marked constrictions arise at intervals—about five in a revolution. They are inclined slightly forward and interfere some-what with costation. They have a thick bolster before and behind. Ribs numerous, high, steep-sided, and narrowly rounded. Some of the ribs begin at umbilicus and nearly always bifurcate at top of the wall and interstitial ribs frequently begin at this point. Ribs at first incline forward, but at a distance of one-third of height of flank they bend back and become almost exactly radial. They pass straight over umbilicus without any diminution in size and without any bend. Constrictions have such a pronounced bend forward that they may interfere with as many as seven ribs; they are nearly straight, but bend slightly forward at about the middle, and pass over periphery with a strong forward curve. There are about fourteen umbilical tubercles in a half-whorl, and most of the ribs originate from them.

Suture-line is very much divided but is clearly of the type of Dalmasiceras, though the external lobe is of far greater importance. It can also be compared with the Desmoceras difficile and beudanti type, which Kilian and Reboul regard as derived from a Hoplitid ancestry (46, p. 17, footnote). First lateral lobe of great depth and importance, and markedly inequilateral hough bifid. There are two prominent secondary saddles, one on each

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side of median line of lobe. The external of these as well as the other elements of the lobe on external side are much larger than those on internal side. Second lateral saddle small and much affected by development of umbilical tubercles. Auxiliary saddles small and progressively inclined, and thus suture-line forms a prominent and deep umbilical lobe. None of the specimens show internal portion of suture-line. Saddles all deeply bifid but not quite symmetrically. In external saddle exterior side is more strongly developed than interior side. In the first lateral saddle, however, the reverse is the case, interior portion being larger and more developed than exterior. Median saddle considerably frilled.

This species is clearly quite closely related to Kossmaticeras (Madrasites) bhavani var. densicostatum, which Kilian and Reboul have described from Seymour Island, but costation is a little coarser and umbilicus somewhat wider. The suture-line of that species has not yet been drawn, but reasons have been given on a previous page for thinking that it should not be placed in the genus Kossmaticeras, and that it is closely related to Puzosia.

The type specimen was sent to Professor Kilian, and after a brief examination of it he classed it as Kossmaticeras (Madrasites) bhavani var. densicostatum; but it appears to me that the costation and diameter of umbilicus are sufficient to distinguish it from the species bhavani. Further, the nature of the suture-line is entirely different from that of all the New Zealand species of Madrasites, and is certainly most distinct from that of M. bhavani given by Kossmat (28, pl. 8, figs. 5, 6), of which, however, Kilian and Reboul say, “La ligne suturale de notre espéce est bien conformé a celle du type” (46, p. 29).

This species is quite distinct from K. haumuriensis Hector as described and figured by Woods (57, p. 34, pl. 19, fig. 5a; pl. 20, fig. 1), for the suture-line of that species is of the K. bhavani (Stoliczka in Kossmat) type; the costation also is of a type different from that shown in the present species. No species that seems to be closely related to this one has yet been recorded from the other countries in which the Indo-Pacific fauna of Ammonites has been described, unless the species Desmoceras hoffmani from California be regarded as similar. It seems, however, that this species, in spite of its compressed form, is a true Desmoceras. Only one good specimen of Maorites suturalis has yet been found, though with it have been discovered a few fragments of other specimens at Bull's Point, the typical locality.

Puzosia Bayle.

Ammonites mayorianus was taken by Bayle as the genotype of this genus. Of it de Grossouvre (19, p. 171) says, “I keep the name Puzosia for the forms of a group of ammonites (subplanulata) which have a moderate umbilicus the whorls of which present transverse furrows and sickle-shaped ribs, which, however, are absent near the umbilicus and are marked only on the external region of the flanks. The suture-line offers a complete similarity to that of Desmoceras but is more reduced, and the first lateral lobe is longer than the ventral lobe. The lobes are trifid, and are somewhat more upright than in Desmoceras. The saddles, which are almost all similar, are divided into two parts by a deep lobule.” He takes the suture-line of D. subplanulatum as typical. Sarasin (29A, p. 793) says that, as the genus had not been clearly defined, it had been little adopted by palaeontologists. He characterizes it as follows: “La coquille est

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moyemment involutée avec les tours arrondis ou légèrement aplatés sur les côtés, toujours arrondis sur le pourtour externe, le pourtour de l'ombilic n'est jamais caréné et generalment arrondi, les tours sont marqués de nombre variable des constrictions droits ou flexueuses et regulièrement espacées entre les sillons. La coquille est tantôt Iissée tantôt ornée de fines côtes, attenuée sur la partie interne des tours. Les cloisons sont toujours très découpées, le lobe ventral est le même longueur ou un peu plus court que le premier latéral; la selle ventral trés reserrée à sa base s'élargit à la partie supérieure qui est profondement divisée par un lobe accessoire. Le premier lobe latéral est symétrique ou subsymétrique; la première selle latérale est généralment un peu plus elevée que la selle ventrale; sa partie interne est presque constamment plus haute que sa partie externe; le second lobe latéral, moins long et large que le premier, est toujours très disymmétrique; la deuxième selle latérale est moins haute que la précédente, elle est encore trés découpée. Ensuite viennent trois à cinq lobes auxiliaires qui sont tantôt droits ou tantôt au contraire très obliques.”

He classifies Desmoceras in four groups—(1) D. difficile, (2) D. beudanti, (3) D. emmerici, (4) D. mayorianum d'Orb. = Amm. planulatus Sow. The last two of these divisions are considered by him to constitute the subgenus Puzosia.

Zittel (11A, p. 465) divided the genus Desmoceras into five groups—(1) D. beudanti, (2) D. difficile, (3) D. emmerici, (4) D. planulatum, (5) D. gardeni. Kilian and Reboul refer the beudanti and difficile groups to the family of Hoplitidae, the mayoriana and angladei groups to the Phylloceratidae.

Kossmat in 1897 (28, p. 106) distinguishes between three groups of Desmoceratids: (1) Desmoceras emmerici Rasp. with a very regular suture-line. The separate lobes and saddles decrease little by little and extend to the umbilicus. (2) D. planulatum Sowerby (Puzosia Bayle). A distinctly-developed depressed umbilical lobe. The external lobe is almost always a good deal shorter than the first lateral lobe, and this makes it appear as though the external saddle were inclined outwards. The various lobe elements are not arranged with any regularity. He states that this group is closely related to Ammonites beudanti d'Orb. on the one hand, and with Holcodiscus through H. pondicherryianus on the other, as well as with Pachydiscus. (3) D. gardeni (Hauericeras de Grossouvre) includes keeled forms from the Upper Chalk, which in their other characters come very close to the group Ammonites planulatus.

Kihan and Reboul make the following comment (46, p. 17): “On réunit souvent á tort nous semble-t-il, en une même groupe, les Desmoceras s. str. (groupe beudanti-difficile) et les Puzosia (P. angladei, P. mayoriana, etc.) ces deux rameaux ne semblent cependant avoir entre eux aucun rapport genetique; le premier dérive sans doute des Holplitides (sensu lato) specialement de Leopoldia, et le second peutêtre des Phylloceratides par l'intermediare de Sowerbyceras (Tortisulcati) et de Silesites?”

Zittel in 1895 and Hyatt in 1913 included Puzosia and Hauericeras in the Desmoceratidae. This relationship was the one adopted also by Yabe in 1903 (37, p. 30).

Pervinquière (“Sur quelques Ammonites du Crétacé Algerien,” Mem. Soc. Geol. Fr., vol. 17, 1910, p. 31) appears to use Puzosia in the sense defined by Sarasin.

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Jacob (44, p. 26) divides Desmoceras into four groups, the last of which is Puzosia, with the genotype P. mayoriana, which has a symmetrical lobe. This author (p. 55) places several of Sarasin's second group of Desmoceras in Sonneratia, which is referred to the Hoplitidae.

Spath in 1922 makes the following remark (54, p. 120): “The genera Pachydiscus, Parapachydiscus, Parapuzosia, Kossmaticeras, and the many allied developments can all be derived from Desmoceratid stocks which persisted during the Upper Cretaceous.”

In spite of the weight of these authoritative opinions, and with comparatively a small amount of material to study, the author, relying on the character of the suture-line (both external and internal), as well as on the form of the shell, is inclined to regard Puzosia, Hauericeras, and Maorites n. gen. as derived from the Hoplitidae sensu lato.

Puzosia angusta n. sp. (Plate 22, fig. 5; Plate 41, fig. 1.)

Compare—

1865.

Ammonites durga Forbes, in Stol. (11, p. 143, pl. 71, figs. 6, 7).

1898.

Puzosia compressa Koss. (28, p. 119, Taf. 18, fig. 4 = Ammonites durga Forbes, in Stol.).

Dimensions :—

[The section below cannot be correctly rendered as it contains complex formatting. See the image of the page for a more accurate rendering.]

A. B.
Diameter 143 100 190 100
Height of last whorl 52 36 64 34
Width of last whorl 18 12.5 34 18
Umbilicus 53 37 74 39

A, Puzosia angusta n. sp., Bull's Pomt, Kaipara Harbour, N.Z.; B, Puzosia compiessa Koss. (28, p. 119).

The dimensions given above emphasize the feature of the high and narrow whorl, which seems to be more extreme than in any other species of this genus of which descriptions are available. Involution nearly one-half, and whorls rapidly increasing in height. Flanks nearly flat and periphery sharply rounded, with the broadest point about two-thirds of distance from umbilicus to periphery. Umbilical wall short but vertical, passing into flank over a sharp angle of a little more than 90°.

Ornamentation: Lower two-thirds of whorl without costation, but upper third with numerous low rounded ribs arising without any tubercles or projections on the shell. First they are directed slightly forward, but they soon bend to a much more acute angle, and, though they diminish in size towards periphery, they distinctly pass over it with a sharp forward loop. Prominent constrictions, apparently five in a revolution, take their rise from umbilicus, and each of them has a high bolster behind. At first the constrictions slope forward at a moderate angle, and near top of flank they bend farther forward and become parallel with ribs and pass over periphery with a sharp curve forward.

Suture-line of the typical Puzosid form, not dissimilar from that of P. compressa, but more finely divided. In the only specimen that shows a suture-line the external saddle, unfortunately, cannot be seen. First lateral lobe deep and, as usual, wanting in symmetry. First lateral saddle almost equally bifid, and auxiliary lobes and saddles, few in number, form a deep umbilical lobe.

This species is certainly closely related to Puzosia compressa Koss., which comes from the Utatur formation of India, regarded as of Cenomanian

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age. It appears to be confined to this formation, for the small specimen figured by Stoliczka is classified by Kossmat as Hauericeras rembda.

Three fragmentary specimens only have been found, and all come from the north side of Bull's Point.

Parapuzosia Novak, 1913.

Novak states that the inner whorls have the typical Puzosia form with constrictions. These disappear in the outer whorls and ribbing is developed (45, p. 350).

Novak established this genus for the Puzosia demsoni group; but, as Spath points out, Novak described and figured P. daubréei only, and consequently Spath takes P. daubréei as the genotype of Parapuzosia. This genus, he says, has the course of the radial line and the strongly projected constrictions of the P. subplanulata type, different from the straight ornamentation of the Campanian (54, p. 127). He includes in this genus the Indian species P. gaudama Forbes and P. indopacifica Koss. In both these species the ribs cross the periphery and there are no tubercles.

At the same time Spath established the genus Kitchinites, including therein K. pondicherryanus Koss., K. japonicus Spath = Desmoceras gaudama (Forbes) Yokoyama, as well as K. darwini Phil., all rather coarse-ribbed types, with the ribs crossing the periphery though they are absent on the lower part of the flanks. There are no tubercles. The first of these three species has a typical Madrasites suture-line. K. darwini, however, has a suture-line of Puzosid type, and the strong projections of the constrictions of that type.

The New Zealand species Parapuzosia brevicostata appears to be closely related to P. gaudama on the one hand and to Kitchinites darwini on the other; but I am inclined to retain it in the genus Parapuzosia, as explained later.

Parapuzosia brevicostata n. sp. (Plate 24, fig. 3; Plate 43, fig, 2.)

Compare—

1845.

Ammonites gaudama Forbes (1, p. 113, pl. 10, fig. 3).

1865.

Ammonites planulatus Sowerby, in Stol. (11, p. 134, pl. 67, fig. 1).

1890.

Desmoceras gaudama Forbes, in Yokoyama (17, p. 184, Taf. 18, fig. 14; Taf. 19, figs. 5 a, b) = Puzosia indopacifica Koss. (28, p. 117) = Kitchinites japonicus Spath (54, p. 127).

1909.

Puzosia sp. Kilian and Reboul (46, p. 19).

1895.

Puzosia darwini Steinmann (26, p. 73, Taf. 5, figs. 3 a, b, c, fig. 4) = Kitchinites darwini in Spath (54, p. 127).

1922.

Parapuzosia gaudama Forbes, in Spath (54, p. 126).

Dimensions :—

[The section below cannot be correctly rendered as it contains complex formatting. See the image of the page for a more accurate rendering.]

A. B. C. D.
Diameter 56 100 89 100 56 100 190 100
Height of last whorl 26 46 37 42 23 41 64 34
Width of last whorl 13 26 27 30 19 34 34 18
Umbihcus 19 34 25 28 18 32 74 39

A, Parapuzosia brevicostata, specimen from Nedler's, Whangaroa, N.Z.; B, Parapuzosia gaudama (28, p. 115); C, Puzosia planulata (28, p. 112); D, Puzosia compressa (28, p. 119).

Periphery gently rounded, the curve passing rapidly into a long flat flank. A short curve at the edge of umbilicus passes quickly into a vertical umbilical wall.

Ornamentation: A number of low rounded ribs commence at umbilicus and are at first directed radially, but towards outer side of flank they curve

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forward and become thinner, and are almost lost at periphery. At the point where the forward bend commences a secondary rib arises between each pair of primary ribs. Deep constrictions arise at intervals, but only two in a half-whorl. They are at first radial, but soon bend forward more strongly than ribs, and are continuous across periphery, which they cross in a strong almost V-shaped curve.

Suture-line has a moderately deep external lobe, which is deeper than is usual in Puzosia, though little more so than in Parapuzosia gaudama (28, pl. 16, fig. 4) and Puzosia crebrisulcata (28, pl. 18, fig. 2). First lateral lobe, as usual, is of great importance, but in this species is rather more symmetrical than usual. External saddle rather wide, bifid, with a rather wide median lobe. Second lateral lobe very small, and three auxiliaries much inclined, forming a deep umbilical lobe.

This species differs from P. gaudama in its narrower form, distinction between primary and secondary ribs, and in the failure of the ribs to maintain their strength across periphery. The same characters distinguish it from P. crebrisulcata, and in addition the small number of constrictions it shows. Kitchinites darwini from Quiriquina has rather stouter ribs which cross periphery, a broader form, more numerous constrictions, and a suture-line more finely divided. The variety P. gaudama var. intermedia does show primary and secondary ribs, and, while it is not so narrow as P. compressa, it has a smaller umbilicus. P. compressa, also, has little sculpture (28, p. 119).

Suture-line shows a general similarity to that of P. gaudama, but its lobe elements are more nearly symmetrical, the external lobe is more transgressive, and median saddle is more frilled. P. stoliczkai Koss. has a median saddle that is nearly simple, and its ribbing consists of wide low rounded ribs.

A single specimen only, in indifferent state of preservation, has been found at Whangaroa.

Parapuzosia ordinaria n. sp. (Plate 24, fig. 4; Plate 31, figs. 6, 7.)

Compare—

1885.

Ammonites bhima Stol. (11, p. 137, pl. 69, figs. 1–3).

Dimensions:—

[The section below cannot be correctly rendered as it contains complex formatting. See the image of the page for a more accurate rendering.]

A. B. C.
Diameter 28 100 48 100 130 100
Height of last whorl 12.5 45 41 46
Width of last whorl 9 32 33 34
Umbilicus 8 28 30 23

A, Parapuzosia ordinaria Batley, Kaipara Harbour, N.Z.; B, Ammonites bhima Stol. (11 p. 137); C, Ammonites bhima Stol. (11, p. 137).

Shell small; involution nearly one-half; whorls much higher than wide and rapidly increasing. Umbilical wall at first steep, then gently sloping, with the thickest part of whorl rather more than half the distance from umbilicus to sharply-rounded periphery. Umbilicus shallow.

Ornamentation: Surface of shell practically destitute of ornament except for very fine striations or growth-lines, which at first bend backward but on the flank curve forward and pass over periphery with a sharp forward curve. This, however, does not prevent the shell from having a bright and polished appearance, and a strong lens is required to make the striations distinct. Seven constrictions in the last whorl, bordered behind by a rounded bolster rib. They are directed forward at first, and on upper

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part of flank they bend still more forward, finally passing over periphery in a sharp forward curve.

Unfortunately the suture-line is not well preserved. External lobe shallow and narrow. First lateral lobe a good deal deeper and very wide, and nearly symmetrical. Saddles bifid but not deeply dissected. Second lateral saddle already on umbilical slope. Three auxiliary saddles all strongly inclined and forming a deep umbilical lobe.

The sloping nature of umbilical wall, the smooth surface, as well as the relatively simple suture-line, distinguish this from all other species of Parapuzosia of which descriptions can be found in the available literature. It seems to be closer to Puzosia bhima Stol. (11, p. 137, pl. 69, figs. 1–3) than to other species. However, this species comes from the Cenomanian, and is apparently related to Ammonites octosulcatus in the Grey Chalk in the Isle of Wight. It is probable that the resemblance is more apparent than real.

A single specimen has been found at Batley.

Tainuia n. gen.

Genotype: Tainuia aucklandica n. sp.

Shell with flat flanks, especially in the inner whorls. Costation strong and coarse, with ribs strongly inclined forwards. Five constrictions in a whorl running parallel to ribs. Umbilical and siphuncular tubercles on each rib. On each rib a number of rounded tubercles. Suture-line much dissected. Median saddle rather frilled. First lateral lobe bipartite but not quite symmetrical, much deeper than external lobe. Saddles bifid and suture-line sloping backward rapidly from edge of umbilicus.

At first sight the ornamentation of this form suggests that it belongs to the genus Acanthoceras; but the constrictions distinguish it from that genus, and the distinction is emphasized by the suture-line with its deep unforked first lateral lobe. On the other hand, Kossmat has a seventh group of species of Acanthoceras (28, p. 25), “VII Arten aus der Verwand-schaft des Acanthoceras vicinale,” which has the main characters of form and ornamentation (except the constrictions) and the deep slightly unsym-metrical bipartite first lateral lobe. This new genus Tainuia is evidently close to this group, the members of which are far from typical species of Acanthoceras. This is also true of the compressed variety of Acanthoceras rotomagense Stol. (11, pl. 34, figs. 5 a–c), which, however, is placed by Kossmat under A. gothicum, a much less compressed form with a very different suture-line (28, p. 198, Taf. 25, figs. 3 a, b).

In external form A. pseudodeverianum Jimbo (22, p. 32, Taf. 5, figs. 1 a, b) closely resembles the genotype, but here again the suture-line is very distinct.

The genus resembles Parapuzosia, in respect of its compressed form, inclination of the constrictions, and in the nature of the suture-line itself. On the other hand, it is wholly different from Parapuzosia in the character of its ornamentation. In the absence of specimens of the Indian species referred to above it is not possible to offer any suggestions as to whether any of them should be included in this genus. The suture-lines as drawn by Stoliczka and Kossmat do not show sufficient detail to make any close comparison, but it is probable that they are far less dissected than that of Tainuia. In the three forms Acanthoceras discoidale Koss., Acanthoceras vicinale Stol., and the compressed variety of Acanthoceras rotomagense

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de France in Stol. (non A. gothicum Koss., 28, p. 198, which has a very different suture-line), there is often an absence of the median line of tubercles. This, however, must not be regarded as too important a difference. Kossmat, for instance, says, “das Fehlen der siphonalen Knotenreihe bilden ebenfalls keinen durchgreifenden Unterscheid.”

A fragment of a specimen of the only species was sent to Professor Kilian, who notes, “une forme adulte [of Gunnarites antarcticus] prenant outre les crénelures des côtes, des tubercles siphonaux produisant une convergence vers le type Acanthoceras” (55, p. 175). I find myself unable to adopt this view.

This genus is certainly similar in some respects—so far, at any rate, as ornamentation is concerned—to Mortoniceras (Meek), a genus which is diagnosed by de Grossouvre as follows: “Ce sont en général des coquilles dont le section des tours est plus élevé que large de forme subquadrangu-laire, à bord externe large et ornée sur la ligne siphonale d'une petite quille arrondie très peu saillante. La cloison rassemble par certains traits à celle des Acanthoceras sauf que le premier lobe latéral est arrondi à son extrémité et termine par des digitations avant tout à peu prês la même valeur de sorte que l'on n'y distingue pas, ou tout ou moins très peu nettement la fourche terminale caractéristique des Acanthoceras et des Stohczkaia.”

Whilst in general form not far distant from Mortoniceras, there is no keel, but a well-defined row of ventral tubercles. However, von Heupen (52, pp. 42, 43) states that in Peroniceras and Acanthoceras a keel may be replaced by a row of tubercles. Thus this distinction falls to the ground. In this genus there are five constrictions in a whorl. The suture-line, however, is much more divided than that of Mortoniceras as figured by Spath and von Heupen. The median saddle, in particular, is frilled. The first lateral lobe is bifid, not forked. There are three auxiliary saddles, and the suture-line falls backward considerably from the umbilicus. On the other hand, the suture-line is very similar to that drawn by Crick of Mortoniceras soutoni (Baily) (53, pl. 20, fig. 4). Spath says of this, “The suture-line of an example of M. soutoni Baily, very close to Baily's type, with small umbilicus and comparatively smooth outer whorl, is given for comparison, since it differs from that figured by Woods and from the original drawing by Baily.”

“Tainui” is the name of one of the canoes in which the ancestors of the Maori navigated the Pacific Ocean to New Zealand.

Tainuia aucklandica n. sp. (Plate 24, fig. 2; Plate 34, fig. 3; Plate 46, figs. 1–3.)

Dimensions:—

[The section below cannot be correctly rendered as it contains complex formatting. See the image of the page for a more accurate rendering.]

A. B. C. D.
Diameter 195 100 125 100 121 100 210 100
Height of last whorl 71 36 43 34 42 35 90 43
Width of last whorl 56 29 34 27 35 29 72 34
Umbilicus 74 38 42 34 42 35 78 37
E. F. G. H.
Diameter 65 100 134 100 139 100 76 100
Height of last whorl 46 66 49 60 43 32 42
Width of last whorl 41 38 28 38 27 31 41
Umbilicus 26 24 18 38 27 26 34

A, B, Tainuia aucklandica from Bull's Point, Kaipara, N.Z.; C, Tainuia aucklandica from Whangaroa, N.Z.; D, Acanthoceras pseudo-deveiianum Jimbo (22, p. 32); E, Ammonites compressus Stol. (11, p. 66, pl. 34, fig. 5); F, Ammonites vicinale Stol. (11, p. 84, pl. 44; 28, p. 200, Taf. 25, fig. 2); G, Acanthroceras discoidale Koss. (28, p. 201, Taf. 25, fig. 1); H, Acanthroceras gothicum Koss. (28, p. 198, Taf. 25, fig. 3).

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It will at once be seen from the table given above that Tainuia aucklandica in its dimensions comes quite close to Acanthoceras pseudo-deverianum Jimbo, and among the Indian species it comes closest to Acanthoceras discoidale Koss.

Shell large, discoid, with whorls much higher than wide. Involution about five-eighths. Umbilical wall steep, but sides soon rounded off into flanks, which are almost flat and slope gradually into a curve passing rather sharply over periphery. The thickest part is about one-third of the height from umbilicus.

Ornamentation: The shell is strongly ribbed—about twenty-one in each half-revolution. Most of ribs commence as moderate rather lamellar tubercles at top of umbilical wall, and pass over flanks almost radially or with a slight forward inclination, and over periphery with a distinct forward curve. There are four knots on each rib between umbilical tubercle and siphuncle, which increase gradually and uniformly in size towards siphuncle. The first is situated at about one-third of height from umbilical tubercle; the others divide the remaining space about equally, but are not quite regular in position. On median line there is an additional row of tubercles. Between each pair of ribs which arise from tubercles there is always one interstitial rib, which commences just below first tubercle of flank and has tubercles similar to those on ordinary ribs. Six constrictions in a revolution, and each of these has a strong bolster before and behind, relatively slightly tuberculated. The posterior of these intersects one interstitial rib. Some indistinct striations between ribs on body-chamber, which is rather more than half a whorl in size.

Suture-line much dissected. Median saddle somewhat frilled, and a great deal shorter than external saddle, which is conspicuously bifid. First lateral lobe very deep and conspicuously bifid, though the two sides are not symmetrical. Second lateral lobe not nearly so deep, and auxiliary lobes small and a good deal inclined. The other saddles as far as second auxiliary are also bifid. Four auxiliary saddles only are present. Taking a broad view, it may be said that the suture-line is much more complicated than that of Acanthoceras; the first lateral lobe is much deeper and of more importance than in Madrasites, but has these qualities in a less degree than Maorites. The external lobe is not so deep as in Parapachydiscus, and there is a more decided slope towards the umbilicus. The first lateral lobe is distinctly wanting in the forked form that is so characteristic of Acanthoceras and Mortoniceras, to which genera the external form of Tainuia shows a good deal of resemblance, though the umbilicus is noticeably smaller and the periphery is far more rounded.

Three specimens of this form have been found: the type comes from Whangaroa; the other two from Bull's Point, Kaipara Harbour. The type is in the Auckland Museum.

Parapachydiscus Hyatt emend Spath (54, p. 122).

Genotype: P. gollevillensis D'Orb.

I have been unable to find a diagnosis of the characteristics of this genus, and give the following short abstract of de Grossouvre's description of the genotype (19, p. 214, pl. 29, fig. 10; pl. 31, fig. 9):—

Shell discoid compressed, involution more than one-half. Umbilicus of moderate size with vertical walls. Whorls much higher than wide, and

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in the young forms quite smooth. Umbilical ribs few (nine in a whorl). Ribs of peripheral region short, and become less prominent in the more mature individuals. Suture-line much the same as in Pachydiscus. Median saddle rather frilled. External lobe not quite so deep as first lateral lobe, which is symmetrical. Saddles nearly symmetrically divided by a deep secondary lobe. Frilling of suture-line extremely complex and intricate.

Spath in a critical survey of this genus establishes a large number of subgenera, but it seems that this species should be included in his Parapachydiscus sensu stricto (54, p. 122).

All the species of this genus are found in the Campanian or the Maestrictian.

Parapachydiscus rogeri n. sp. (Plate 25, fig. 2; Plate 47, figs. 1, 2.)

Compare—

1921.

Parapachydiscus aff. wittekindi Sch., in Spath (53, p. 229, pl. 24, fig. 1).

1885.

Parapachydiscus tweenianus Stol. (11, pl. 54, fig. 3).

1895.

Parapachydiscus tweenianus Stol., in Koss. (28, p. 102).

The specimens of this large species are unfortunately so imperfect that approximate measurements only can be given. The most complete specimen represents perhaps only one-eighth part of a complete individual, but it measures 350 mm. by 300 mm. by 120 mm. and weighs about 40 kilograms. This fragment is entirely septate, and it is probable that the complete individual with the body-chamber would be as much as 774 mm. in diameter. Involution considerable, but the proportion cannot be stated. Flanks gently rounded, the curve gradually increasing as the periphery is approached. Lower part of umbilical wall is almost vertical, but afterwards slopes off gradually to periphery. The surface has large low rounded ribs. In the portion nearest to periphery that is shown in the specimens the distance from the crest of one rib to that of the next is 46 mm. The ribs arise at base of umbilical wall and are at first directed backwards at a sharp angle, but they soon bend, and at about one-third of flank they become radial and maintain this direction as far as can be seen. Here and there a faint striation can be seen parallel to the ribs. The shell matter close to umbilicus is as much as 5 mm. in thickness.

Suture-line: Unfortunately the greater part of the specimen is considerably eroded, and it is not possible to see the details of the external lobe or of the external saddle. First lateral lobe deeper than external lobe and nearly symmetrical. Second lateral lobe also deep, but first auxiliary lobe is far shallower; beyond that the suture-line cannot be seen. Secondary lobe in saddles extends rather less than half-way to base, and the two divisions into which it splits the saddle are not quite equal. In external saddle exterior half is larger than interior, but in first lateral saddle the reverse is the case. Both saddles and lobes are complexly divided.

Ornamentation resembles that of the species from Zululand compared by Spath with P. wittekindi Schluter (53, p. 229, pl. 24, fig. 1). In Parapachydiscus rogeri, however, the ribs are carried right down into umbilicus with a strong forward sweep, whereas in the Zululand species they disappear on the edge of umbilical slope. Suture-line of this species is not very different from that of P. quiriquinae Phil. (26, p. 74, pl. 6, fig. 3 a, b, text-fig. 5), though it cannot be seen whether the inner whorl is

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tuberculate as in that species, which also has more numerous ribs, that do not decrease much towards periphery. It resembles P. tweenianus Stol. (11, p. 107, pl. 54) more closely than any of the other of the Indian species. P. tweenianus is said by Kossmat to be similar to a species, apparently unnamed, from Vancouver (28, p. 122).

Only two fragments of this species have been found, both at Bull's Point, one at each end of the exposure of Cretaceous rocks at that place.

Named in honour of the finder, Roger T. Marshall.

Nowakites Spath (54, p. 124).

Genotype: N. carezi de Grossouvre.

The following diagnosis is drawn from de Grossouvre's description of the genotype (19, p. 190):—

Shell discoid compressed. Spire formed of involute whorls which increase rather slowly in height and width. Flanks slightly convex, and external border rounded with a small umbilicus. Ribs very slightly oblique, leaving the umbilical tubercles in pairs. Between the pairs there are usually one or two auxiliary ribs. Occasionally a transverse constriction, wide but not deep. Mature individuals show shorter and shorter auxiliary ribs. Suture-line not known. Occurs in the Coniacian of Corbières.

The genus Nowakites is a division of the genus Parapachydiscus of Hyatt.

Nowakites denticulatus n. sp. (Plate 25, fig. 3; Plate 38, figs. 5, 6.)

Shell in too imperfect a condition to allow of measurements. Shell of moderate size, with aperture a good deal higher than wide. Numerous ribs with high sharp crests and wide rounded intervals. The sharp crests are finely denticulated, but it is only where the state of preservation of the shell is particularly good that this feature can be seen. Ribs arise in pairs from tubercles on edge of umbilicus, but between every pair are one or two interstitial ribs. All of these pass straight over periphery without any noticeable curvature, except where the specimen has been slightly distorted by pressure. Periodic constrictions indistinct.

Only a small portion of suture-line can be seen. It is distinctly of the Parapachydiscoid type, complex and much divided, and with a deep straight first lateral lobe.

The sharp costation and fine denticulations are the dominant features of this species, which in general respects somewhat resembles Kossmaticeras antarcticum var. bhavaniformis Kilian and Reboul from Seymour Island (46, p. 33, pl. 15, fig. 2). I am tempted to compare it with Koss-maticeras (Grossouvrites) gemmatum Hupe from Quiriquina, a specimen of which has been recorded by Trechmann (56, p. 387) from the Selwyn Rapids, in the South Island.

In virtue of its ornamentation, form, and suture-line, K. gemmatum ought, I think, to be placed in the genus Parapachydiscus. Kilian and Reboul remark that it approaches very close to Pachydiscus in the character of the suture-line (46, p. 23, also p. 42). So far as European species are concerned, I am inclined to say that P. sayni de Gross. (19, p. 181, pl. 39, fig. 2) comes nearest to the present species.

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One specimen only has been collected. It comes from the northern side of Bull's Point, Kaipara Harbour, close to the spot where Parapachydiscus rogeri, Ancanthoceras ultimum, and Gaudryceras subsacya were obtained.

Hauericeras de Grossouvre, 1893.

The genus is described by its author as follows: Shells with a large umbilicus. Whorls thin and high, with a keel on the margin. Flanks slightly convex or even flat, without sculpture but showing constrictions more or less clearly. The suture-line is quite analogous to that of Desmoceras, Puzosia, and Pachydiscus. The first lateral lobe is as long as the external lobe (19, p. 219).

Kossmat says that Hauericeras is separated from Puzosia by the sharp external keel, but remarks later that in a young example of Hauericeras rembda the keel is not developed, and that the same is true of young examples of H. gardeni. There is the same development of auxiliary lobes as in Puzosia, which has the external lobe always distinctly shorter than the first lateral lobe, and the first lateral lobe and external saddle are inclined. In Hauericeras the first lateral lobe is the same length or only slightly longer than the external lobe. The external saddle is straight and not regularly bifid (28, p. 122).

Van Hoepen says that in the South African examples the first lateral lobe is distinctly longer than the external lobe. In Puzosia planulata the external saddle reaches farther forward than the first lateral, but in Hauericeras the reverse is the case. He points out that in the smaller whorls the umbilical surface is perpendicular to the plane of symmetry, while in the older whorls it is inclined (52, p. 27).

Yokoyama says that in the Japanese example the lobes are quite irregularly trifid and not so deep as in the Indian example. This asymmetry is noticeable in the South African example (52, text-fig. 5) and in the Indian specimens (11, pl. 33, fig. 4), but not in the Nanaimo example figured by Kossmat (28, Taf. 18, fig. 10).

Hauericeras ngapuhi n. sp. (Plate 24, fig. 5; Plate 43, fig. 3; Plate 45, fig. 3.

Compare:—

1855.

Ammonites gardeni Baily, Quart. Journ. Geol. Soc., vol. 11, p. 456, pl. 9, fig. 3.

1864.

Ammonites gardeni Baily, in Stoliczka (11, p. 61, pl. 33, fig. 4)

1879.

Ammonites gardeni Baily. in Whiteaves (7, p. 102).

1890.

Desmoceras gardeni Baily, in Yokoyama (17, p. 184, pl. 20, fig. 10).

1906.

Hauericeras gardeni Baily, in Woods (40, p. 332).

1909.

Desmoceras (Hauericeras) gardeni Baily, in Kilian and Reboul (46, p. 18).

1921.

Hauericeras gardeni Baily, in Spath (53, p. 238, text-fig. 12).

1921.

Hauericeras gardeni Baily, in Spath (59, p. 50, table).

1921.

Hauericeras gardeni Baily, in van Hoepen (52, p. 27, text-fig. 15).

1922.

Hauericeras gardeni Baily, in Spath (54, p. 129).

The dimensions given below show that the species is closely related to the widely-occurring species Hauericeras gardeni Baily, which has been recorded from so many countries that lie on the border of the Pacific Ocean. At the same time, the differences are certainly great enough to be

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of specific value. In all the three specimens found there is no keel, but this may be due to their immaturity.

Dimensions:—

[The section below cannot be correctly rendered as it contains complex formatting. See the image of the page for a more accurate rendering.]

A. B. C. D. E. F. G.
Diameter 22.2 100 23.5 100 27 100 120 100 26 100 100 79 100
Height of last whorl 9 40 10 42 12 44 30 10 38 35 32 40
Width of last whorl 6.8 30 7 30 8 30 5.75 22 19
Umbilicus 7 31 7 30 8 30 42 10 38 39 27 37

A, B, C. three specimens of Hauericeras ngapuhi from Whangaroa, N.Z.; D, Ammonites durga Forbes = Puzosia compressa Koss. (11, p. 143); E, Hauericeras gardeni Spath (54, p. 130); F, means of measurements of thirty specimens of Hauericeras gardeni by Crick, Spath (54, p. 129): G, Hauericeras welschi de Grossouvre (19, pl. 35, fig. 9).

Shell small, discoid and much compressed. Whorls high and narrow. Umbilical wall nearly vertical, with a sharp angle to the almost flat flank. Periphery evenly rounded, and involution rather more than a third. Umbilicus of moderate size.

Ornamentation: The surface of shell quite smooth except for conspicuous constrictions, which number six in last whorl. They commence at bottom of umbilicus and, directed strongly forward, pass in a straight line to periphery, over which they pass in a sharp forward curve.

Suture-line not very highly divided. First lateral saddle a good deal higher than the others, and auxiliary saddles fall away posteriorly to a distinct umbilical lobe. There are in all eight saddles. First lateral lobe deeper than external lobe and symmetrical. Second lateral lobe straight but much shorter, and auxiliary lobes much inclined. Saddles are rather more regularly bifid than is usual in this genus.

The shape and ornamentation of the three specimens have caused me to place the species in this genus. Unfortunately the shell matter is not preserved on the periphery, and consequently no keel is to be seen—probably it was not developed; though, as pointed out, the small size of the specimens and their probable immaturity may account for this. The table of dimensions shows that Hauericeras ngapuhi has a higher whorl than the related species, but at the same time it is wider and has a smaller umbilicus. As shown in the table on pages 19697, Hauericeras gardeni has a very wide occurrence in the countries that border the North Pacific.

Three specimens, one from Bull's Point and two from Whangaroa.

The Ngapuhi is a famous Maori tribe of New Zealand.

Schluteria de Grossouvre.

This genus was established by de Grossouvre to include some species of the Upper Chalk closely allied to Phylloceras by their form and ornamentation, but their suture-line clearly approaches that of Puzosia and Pachydiscus, and differs entirely from that of Phylloceras in the absence of the large foliaceous terminations (19, p. 216). De Grossouvre, however, as Spath has pointed out (53, p. 46), included in this genus certain species of Phylloceras related to P. nera. Spath has therefore emended the genus, and has taken as the genotype Schluteria larteti Seunes.

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Schluteria rarawa n. sp. (Plate 19, fig. 10; Plate 32, figs. 7, 8.)

Compare:—

1845.

Ammonites diphylloides Forbes, Trans. Geol. Soc., ser. 2, vol. 7, p. 105, pl. 8, fig. 8.

1865.

A. diphylloides Stol. (11, p. 119, pl. 59, figs. 8, 9).

1897.

Desmoceras diphylloides Koss. (28, p. 109, Taf. 19, figs. 8 a, b, c, 9 a, b, c)

Dimensions:—

[The section below cannot be correctly rendered as it contains complex formatting. See the image of the page for a more accurate rendering.]

A. B. C.
Diameter 11 100 22 100 34.6 100
Height of last whorl 6 55 11 50 21.1 58
Width of last whorl 6 55 11 50 16.3 47
Umbilicus 4 18 2.8 08

A, Schluteria rarawa, Kaipara Harbour, N.Z.; B, Schluteria (Desmocerds) inanis Koss. (28, p. 107); C, Schluteria (Desmoceras) crassa van Hoepen (52, p. 21).

Shell small, completely involute, with whorls rapidly increasing. Wall of umbilicus sloping steeply at first but soon rounding off into the flanks, which maintain the same curve. The whole aperture, therefore, is nearly circular.

Ornamentation: Very fine ribs can be distinguished on umbilical slope, the specimens being extremely well preserved. About every fifth is stronger than the others. They curve sharply backward first, then forward, but they disappear about half-way up the flanks. A strong lens is required to make them visible, as to the naked eye the surface appears smooth and polished. Six constrictions in a whorl, which are shallow and bordered behind by a low but wide bolster rib.

Suture-line with nine saddles decreasing gradually and uniformly from periphery to umbilicus. Exterior and first lateral saddle bifid. Lobes symmetrically bifid and much wider than saddles. Lobes uniformly of same depth, and the whole suture-line is linearly radial in direction.

Schluteria simplex from Pondoland has a narrower whorl than this species, but Schluteria crassa from the same country comes nearer to it in form. The species certainly comes close to Desmoceras loryi from Seymour Island, described by Kilian and Reboul (46, p. 18, pl. 1, figs. 4, 5), though all the specimens that have been found in New Zealand are much smaller. This species is much more inflated than S. diphylloides Forbes and than S. inane Forbes. The suture-line is spaced out like that of S. phyllimorphum Koss., but the form and size are quite different. The suture-line is not unlike that of S. diphylloides and S. inains.

A specimen in the collection of the Geological Survey of New Zealand, which was found by McKay near Awanui, on the east coast of the North Island, comes very close to this species, but it is badly preserved. Several specimens have been obtained from Batley and Bull's Point.

Importance of Suture-lines.

The suture-lines that are represented in Plates 1925 have been drawn with great care, and are thought to be nearly exact, though the projection on to a flat surface offers difficulty, and certainly gives rise to some error. As far as practicable, mechanical methods were employed, and errors in proportions are thereby greatly reduced. It is recognized that too much reliance cannot be placed on the details of the form of the suture-line for purposes of identification: ornamentation and proportions of the shell must have full consideration.

Suture-lines of the following species:—

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Fig. 1.—Baculites rectus n. sp. Bull's Point.
Fig. 2.—Ptychoceras zelandicum n. sp. Whangaroa.
Fig. 3.—Diplomoceras wakanene n. sp. Bull's Point.
Fig. 4.—Phylloceras nera Forbes. H. 19; W. 9. Batley.
Fig. 5.—Phylloceras bistriatum n. sp. H. 19; W. 19. Bull's Point.
Fig. 5a.—Internal suture-line.
Fig. 6.—Phylloceras forbesianum d'Orb. H. 17; W. 16.5. Batley.
Fig. 7.—Phylloceras radiatum n. sp. H. 22; W. 15. Bull's Point.
Fig. 7a.—Internal suture-line.
Fig. 8.—Phylloceras minimum n. sp. H. 10.5; W. 9.
Fig. 8a.—Internal suture-line.
Fig. 9.—Zelandites kaiparaensis n. sp. H. 7.6; W. 6. Bull's Point.
Fig. 9a.—Internal suture-line.
Fig. 10.—Schluteria rarawa n. sp. H. 4.75; W. 5.25. Batley.

Suture-lines of the following species:—

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Fig. 1.—Pseudophyllites indra Forbes. H. 22; W. 21. Bull's Point.
Fig. 2.—Pseudophyllites whangaroaensis n. sp. H. 16; W. 18. Whangaroa.
Fig. 3.—Gaudryceras politissimum Koss. H. 9; W. 7.5. Bull's Point.
Fig. 4.—Gaudryceras propemite n. sp. H. 7; W. 9.
Fig. 4a.—Internal portion of suture-line. Bull's Point.
Fig. 5.—Tetragonites margaritatus n. sp. H. 5.5; W. 6.25. Batley.
Fig. 6.—Tetragonites latus n. sp. H. 6.25; W. 10. Batley.
Fig. 6a.—Internal portion of suture-line. H. 4; W. 8.
Fig. 7.—Gaudryceras particostatum n. sp. H. 7; W. 6.5. Bull's Point.
Fig. 7a.—Internal portion of suture-line. H. 8; W. 8.
Fig. 8.—Gaudryceras subsacya n. sp. H. 5; W. 7.5.
Fig. 8a.—Internal portion of suture-line. H. 7; W. 9.
Fig. 9.—Vertebrites murdochi n. sp. H. 5; W. 10. Hokianga.
Fig. 9a.—Internal portion of suture-line.
Fig. 10.—Gaudryceras crenatum n. sp. H. 4.75; W. 6.5. Bull's Point.
Fig. 11.—Tetragonites simplex n. sp. H. 5.75; W. 5.5. Batley.
Fig. 11a.—Internal portion of suture-line. H. 3; W. 3.

Suture-lines of the following species:—

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Fig. 1.—Jacobites whangaroaensis n. sp. H. 44; W. 35. Whangaroa.
Fig. 2.—Jacobites angularis n. sp. H. 21; W. 22.5. Bull's Point.
Fig. 3.—Jacobites anderssoni K. & R. H. 12; W. 11.
Fig. 3a.—Internal portion of suture-line. H. 5; W. 5.
Fig. 4.—Neomadrasites nodulosus n. sp. H. 7.5; W. 9.25. Bull's Point.
Fig. 4a.—Internal portion of suture-line.
Fig. 5.—Jacobites minimum n. sp. H. 3; W. 2.2. Batley.
Fig. 6.—Madrasites multicostatus n. sp. H. 9.5; W. 10. Bull's Point.
Fig. 7.—Madrasites regularis n. sp. H. 10; W. 10. Bull's Point.
Fig. 8.—Gunnarites nordenskjoldi K. & R. H. 5; W. 5. Batley.
Fig. 9.—Brahmaites rotundus n. sp. H. 5; W. 8. Batley.
Fig. 10.—Tetragoniles tetragonus Koss. H. 16; W. 17. Bull's Point.
Fig. 11.—Pseudophyllites whangaroaensis n. sp. Internal portion of suture-line. H. 6.5; W. 7.5. Whangaroa.
Fig. 12.—Madrasites fortior n. sp. Whangaroa.

Suture-lines of the following species:—

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Fig. 1.—Gunnarites inflatus K. & R. H. 38; W. 32. Batley.
Fig. 1a.—Internal portion of suture-line H. 35; W. 31. Bull's Point.
Fig. 1b.—Suture-line of juvenile form. Bull's Point.
Fig. 2.—Gunnarites zelandicus Marshall. H. 24; W. 22. Specimen somewhat eroded.
Fig. 3.—Gunnarites antarcticus Stuart Weller. H. 35; W. 27. Batley.
Fig. 4.—Internal suture-line of Jacobites angulans n. sp. H. 21; W. 25.
Fig. 5.—Puzosia angusta n. sp. H. 25; W. 9.

Suture-lines of the following species:—

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Fig. 1.—Maorites tenuicostatus Marshall. H. 51; W. 35.5. Batley.
Fig. 1a.—Internal portion of suture-line. H. 39; W. 35.
Fig. 2.—Jacobites waitapuensis n. sp. H. 34; W. 30. Whangaroa.
Fig. 3.—Maorites suturalis n. sp. H. 26; W. 17. Bull's Point.

Suture-lines of the following species:—

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Fig. 1.—Maorites densicostatus K. & R. H. 21; W. 13. Bull's Point
Fig. 2.—Tainuia aucklandica n. sp. H. 43; W. 34. Whangaroa.
Fig. 3.—Parapuzosia brevicostata n. sp. Whangaroa.
Fig. 4.—Parapuzosia ordinaria n. sp. H. 8; W. 6. Batley.
Fig. 5.—Hauericeras ngapuhi n. sp. H. 9; W. 6. Bull's Point.
Fig 5a.—Internal portion of suture-line.

(Through an unfortunate error tubercles are indicated in fig. 3 in place of fig. 1.)

Suture-lines of the following species:—

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Fig. 1.—Acanthoceras ultimum n. sp. Bull's Point.
Fig. 1a.—Internal portion of suture-line. H. 9.
Fig. 2.—Parapachydiscus rogeri n. sp. H. 220; W. 270 (?). Bull's Point.
Fig. 3.—Nowakites denticulatus n. sp. H. 39; W. 38 (?). Bull's Point.

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Fig. 1.—Phylloceras nera Forbes. × 1 ½.
Fig. 2.—Phylloceras nera Forbes: section from periphery to umbilicus.
Fig. 3.—Phylloceras radiatum n. sp. × 1 ½.
Fig. 4.—Phylloceras radiatum n. sp.: section from periphery to umbilicus.
Fig. 5.—Phylloceras minimum n. sp. Bull's Point. × 2 ½.
Fig. 6.—Phylloceras minimum n. sp.: section.

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Fig. 1.—Phylloceras bistriatum n. sp. Bull's Point. × 2.
Fig. 2.—Phylloceras bistriatum n. sp.: section.
Fig. 3.—Phylloceras forbesianum d'Orb. × 2.
Fig. 4.—Phylloceras forbesianum d'Orb.: section.

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Fig. 1.—Gaudryceras politissimum Koss. Batley. × 1 ½.
Fig. 2.—Gaudryceras politissimum Koss.: section.
Fig. 3.—Gaudryceras propemite n. sp. Bull's Point. × 1 ½.
Fig. 4.—Gaudryceras propemite n. sp.: section.

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Fig. 1.—Gaudryceras subsacya n. sp. Bull's Point. × 1 ¼.
Fig. 2.—Gaudryceras subsacya n. sp.: section.
Fig. 3.—Pseudophyllites indra Forbes. × 1 ¼.
Fig. 4.—Pseudophyllites indra Forbes: section.
Fig. 5.—Pseudophyllites indra Forbes: flank, showing suture-line.
Fig. 6.—Tetragonites epigonus Koss. × 1 ½.
Fig. 7.—Tetragonites epigonus Koss.: section.

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Fig. 1.—Vertebrites murdochi n. sp. × 1 ½.
Fig. 2.—Vertebrites murdochi n. sp.: section.
Fig. 3.—Gaudryceras particoslatum n. sp. × 1 ½.
Fig. 4.—Gaudryceras particoslatum n. sp.: section.
Fig. 5.—Tetragonites margaritatus n. sp. × 1 ½.
Fig. 6.—Tetragonites margaritatus n. sp.: section

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Fig. 1.—Zelandites kaiparaensis n. sp. Bull's Point. × 1 ½.
Fig. 2.—Zelandites kaiparaensis n. sp.: section.
Fig. 3.—Gaudryceras crenatum n. sp. Bull's Point. × 1 ½.
Fig. 3a.—Gaudryceras crenatum n. sp.: section.
Fig. 4.—Brahmaites rotundus n. sp. Batley. × 1 ½.
Fig. 5.—Brahmaites rotundus n. sp.: section.
Fig. 6.—Parapuzosia ordinaria n. sp. Batley. × 1 ¼.
Fig. 7.—Parapuzosia ordinaria n. sp.: section.
Fig. 8.—Diplomoceras wakanene n. sp Bull's Point. × 1 ½.
Fig. 9.—Diplomoceras wakanene n. sp.: section.

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Fig. 1.—Tetragonites latus n. sp. Batley. × 1 ½.
Fig. 2.—Tetragonites latus n. sp.: section.
Fig. 3.—Tetragonites simplex n. sp. Bull's Point. × 1 ½.
Fig. 4.—Tetragonites simplex n. sp.: section.
Fig. 5.—Periphery of Pseudophyllites whangaroaensis n. sp., showing sculpture
Fig. 6.—Pseudophyllites whangaroaensis n. sp.: section.
Fig. 7.—Schluteria rarawa n. sp. Batley. × 1 ½.
Fig. 8.—Schluteria rarawa n. sp.: section.
Fig. 9.—Baculites rectus n. sp. Batley. × 1 ¼.
Fig. 10.—Baculites rectus n. sp.: section.
Fig. 11.—Ptychoceras zelandicum n. sp. Bull's Point. × 1 ½.
Fig. 12.—Ptychoceras zelandicum n. sp.: section.

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[The section below cannot be correctly rendered as it contains complex formatting. See the image of the page for a more accurate rendering.]

Oxybeloceras sp. Mangamuka River. Hokianga. × 3/2.

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Fig. 1.—Acanthoceras ultimum n. sp. Bull's Point. × 1 ¼.
Fig. 2.—Acanthoceras ultimum n. sp.: section.
Fig. 3.—Tainuia aucklandica n. sp.: showing development of tubercles. × 1 ¼.

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Fig. 1.—Madrasites multicostatus n. sp. Bull's Point. × 2.
Fig. 2.—Madrasites multicostatus n. sp.: section.
Fig. 3.—Madrasites regularis n. sp. Bull's Point. × 2.
Fig. 4.—Madrasites regularis n. sp.: section.

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Fig. 1.—Neomadrasites nodulosus n. sp. Bull's Point. × 1 ½.
Fig. 2.—Neomadrasites nodulosus n. sp.: section.
Fig. 3.—Neomadrasites nodulosus n. sp.
Fig. 4.—Jacobites angularis n. sp.: Bull's Point. × 1 ½.
Fig. 5.—Jacobites angularis n. sp.: section.
Fig. 6.—Gunnarites nordenskjoldi K. & R. Batley. × 1 ½.

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Fig. 1.—Jacobites whangaroaensis n. sp. Whangaroa. × ½.
Fig. 2.—Jacobites whangaroaensis n. sp.: section.
Fig. 3.—Jacobites anderssoni K. & R. Bull's Point. × 1 ½.
Fig. 4.—Jacobites anderssoni K. & R.: section.

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Fig. 1.—Madrasites sulcatus n. sp. Batley. × 2.
Fig. 2.—Madrasites sulcatus n. sp.: section.
Fig. 3.—Jacobites minimus n. sp. Batley. × 2.
Fig. 4.—Jacobites minimus n. sp.: section.
Fig. 5.—Nowakites denticulatus n. sp. Bull's Point. Nat. size.
Fig. 6.—Nowakites denticulatus n. sp.: showing costation. × 2.

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Fig. 1.—Gunnarites zelandicus Marshall. Batley. × 1 ½.
Fig. 2.—Gunnarites zelandicus Marshall: section.
Fig. 3.—Gunnarites antarcticus Stuart Weller. Bull's Point. × 1 ½.
Fig. 4.—Gunnarites antarcticus Stuart Weller: section.

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Fig. 1.—Gunnarites inflatus K. & R. Batley. Nat. size.
Fig. 2.—Gunnarites inflatus K. & R.: section.
Fig. 3.—Flank of Vertebrites murdochi n. sp., showing change in costation. × 5.

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Fig. 1.—Puzosia angusta n. sp.: showing costation. Bull's Point. × 2.
Fig. 2.—Puzosia angusta n. sp.: section.
Fig. 3.—Madrasites fortior n. sp. Whangaroa. × 2.
Fig. 4.—Madrasites cumshewaensis? Whiteaves. Whangaroa. × 2.

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Fig. 1.—Maorites tenuicostatus Marshall. Batley. Nat. size.
Fig. 2.—Maorites tenuicostatus Marshall (juv.). Bull's Point. × 2.
Fig. 3.—Maorites densicostatus K. & R. (juv.). Bull's Point.
Fig. 4.—Maorites suturalis n. sp. (juv.). Bull's Point. × 2.

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Fig. 1.—Maorites suturalis n. sp. Bull's Point. × 1 ¼.
Fig. 2.—Parapuzosia brevicostata n. sp. Whangaroa. × 2,
Fig. 3.—Hauericeras ngapuhi n. sp. Bull's Point. × 2.

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Fig. 1.—Jacobites waitapuensis n. sp. Whangaroa. × 1 ¼.
Fig. 2.—Maorites densicostatus K. & R. Bull's Point. Nat. size.

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Fig. 1.—Maorites tenuicostatus Marshall: section.
Fig. 2.—Jacobites waitapuensis n. sp.: section.
Fig. 3.—Hauericeras ngapuhi n. sp.: section.
Fig. 4.—Maorites densicostatus K. & R.: section.
Fig. 5.—Maorites suturalis n. sp.: section.
Fig. 6.—Parapuzosia brevicostata n. sp.: section.

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Fig. 1.—Tainuia aucklandica n. sp. Whangaroa. Nat. size.
Fig. 2.—Tainuia aucklandica n. sp.: fragment showing ornamentation. × 1 ½.
Fig. 3.—Taunuia aucklandica n. sp.: section.

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Fig. 1.—Parapachydiscus rogeri n. sp. Bull's Point. × ⅛. Fig. 2.—Parapachydiscus rogeri n. sp.: showing costation. × ⅓.

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So far as this collection is concerned, it has been found that the suture-line in nearly all cases has given clear indication of the generic position that a species should have, though it hardly enables one to distinguish between such genera as Madrasites, Jacobites, and Gunnarites. It is thought that the time that has been taken in drawing these lines in detail has not been wasted.

It seems that little attention has hitherto been given to the nature of the internal portion of the suture-line. In few researches on collections of ammonites have any drawings been made of them. So far as can be ascertained, Kossmat is the only author who has made any use of them for purposes of classification, and he appears to have done so in one instance only—in the distinction between Gaudryceras and Tetragonites.

In this paper drawings of the internal suture-line of several species will be found, and it is suggested that the form of it may be of great use in assigning species to their proper position in doubtful cases. Spath, however, attaches little or no importance to it: “The stretching-out of the auxiliary elements may only be the result of the adaptation of the suture-line to wider sides, and the raising of the umbilical portion is often found in younger developments” (53, p. 239). This, however, does not hold generally: compare, for example, Gaudryceras and Pseudophyllites.

The form of the internal suture-line is little varied in time and in the widely scattered species of a genus. The internal suture-line of a species of Phylloceras from the Dogger (Zittel, Handbuch, vol. 2, fig. 609) differs but little from those of New Zealand specimens from the Upper Cretaceous. The difference is almost restricted to a reduction in the number of saddles. It is certainly striking that the New Zealand species have the same number of saddles as in Sowerbyceras, and the suggestion thus offered that the New Zealand species should be placed in the latter genus is supported by some other details. Further material for study is, however, needed.

The genus Gaudryceras has the same unusual form of this suture-line in species from India, Japan, South Africa, and New Zealand. The importance of this line that is here suggested is supported by the great variety of form that it presents.

A summary of the variations that have been found in these New Zealand specimens is considered worthy of a special statement:—

Phylloceras: Internal saddle club-shaped. Two lateral saddles, the second with an almost spherical termination. No auxiliaries.

Gaudryceras: A single saddle of uniform width, which is typical in G. subsacya. Those species of Gaudryceras, such as G. semileve, which have a single saddle, increasing greatly in width at the base, should perhaps be placed in a separate genus.

Tetragonites: Two well-developed saddles, as in T. epigonus. Such a species as T. simplex has an additional saddle.

Pseudophyllites: Two saddles, the external one with much greater development than the first lateral.

Vertebrites: Five or six saddles, gradually decreasing in size towards the umbilicus.

Zelandites: A single saddle, wide at the base.

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Jacobites and Gunnarites both have two large saddles, which in the latter genus are much dissected; the antisiphonal lobe is very deep. This form appears to indicate a descent from Acanthoceras.

Madrasites, so far as the New Zealand specimens are concerned, has an internal suture-line but little different from Jacobites, and thus differs much from that figured by Kossmat.

The suture-line of Pachydiscus as drawn by Yabe is quite different from those of the genera mentioned, but it could not be seen in any of the New Zealand specimens.

Maorites, Puzosia, and Hauericeras have the same type of internal suture-line. The lateral saddles and the auxiliaries are situated on the outer slope of the internal saddle, and thus give the appearance of a single complex much-divided saddle. This type of internal suture-line appears as far back as Dalmasiceras, and is continued in Perisphinctes, and is supposed to indicate a relationship to the Hoplitid stock. It is much regretted that the material that was available did not allow of further study.

Geographical Relationship.

In order to make it possible to draw any geographical conclusions from the distribution of the species of ammonites that have been found in New Zealand it is necessary to summarize the facts that have already been recorded in regard to their occurrence in different circum-Pacific countries.

The following percentages of the ammonite fauna of the various countries are represented in New Zealand by identical or closely allied species:—

Number of Species. Number of Related Species in N.Z. Percentage of Species in N.Z. Percentage of N.Z. Species in each.
Aryalur 53 18 34 34
Trichinopoly 26 4 15.5 8
Utatur 89 11 12.5 20
Seymour Island 41 16 39 31
South Patagonia 20 2 10 4
Quiriquina 10 5 50 10
Chico 52 7 13 14
Nanaimo 17 2 11 14
Queen Charlotte Island 27 7 8 4
Japan 47 10 21 19
New Caledonia 12 4 33 8
Pondoland 54 12 22 22
Madagascar 49 5 10 10

It is unfortunate that the Upper Cretaceous ammonites of New Caledonia have not been more fully collected and identified, though Piroutet has done excellent work. The fauna that has been collected by him suggests

– 195 –

that it is rather similar to that of New Zealand, but in the meantime this statement is somewhat hazardous.

As shown in this table, the Seymour Island fauna has remarkable similarities with that of New Zealand, and the conclusion is suggested that there was a continuous coast-line between these countries. This is the belief of Wilckens and others. On the other hand, the Patagonian fauna contains the Hoplites-Placenticeras elements that are absent from New Zealand, Antarctica, and Chile, and in this last country the small fauna that has been discovered shows a closer resemblance to that of New Zealand than any other that has been recorded. No country between Chile and California has yet yielded an Upper Cretaceous ammonite fauna, but in the latter there is the well-known Chico formation. In the lower series of this formation there is a fairly rich fauua, but it is not closely related to that of New Zealand. In the Upper Chico series there are fewer ammonites, and they show a closer resemblance than those of the lower series.

In British Columbia the Queen Charlotte Islands have yielded a fauna that has little resemblance to the one described in this paper, but it is probably of Middle Cretaceous age. On the other hand, the Nanaimo beds are of the Upper Cretaceous period, but still the species that have been obtained from them show little similarity, on the whole, to the New Zealand species.

In the highest Upper Cretaceous ammonite-bearing strata of South India—that is, the Aryalur—a close relationship with New Zealand is again displayed; but in the beds below them—the Trichinopoly series of Lower Senonian age—the resemblance is much less pronounced, and the specific resemblances are fewer. The Utatur beds, which are considered to be of Cenomanian age, have also several species that are closely related to New Zealand forms. The amount of resemblance is, however, decidedly less in the lower than in the upper series.

I have no access to a complete statement of the species that have been found in Madagascar. The works of Spath, Woods, and van Hoepen give full information of the ammonite fauna of Pondoland. It is rather remarkable that these beds contain a fauna that is much more closely related to that of New Zealand than is the fauna of the beds of the same age at Umzamba Hill, in Zululand.

The general geographical impression that is produced is, as might be expected, that the ammonite fauna of this Upper Cretaceous age in the countries closer to New Zealand is more closely related than that of the countries that are more remote. Patagonia is, of course, a striking exception to the general application of this statement, while the species that have been found in Chile and New Caledonia are too few to allow of a satisfactory comparison.

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Table showing the Occurrence of Representative
South Africa. Madagascar. India (Aryalur and Valudayur). India (Trichinopoly). India (Utatur).
1 Phylloceras nera Forbes P. woodsi (Pondoland) P. nera
2 Phylloceras radiatum n. sp. P. umsambiense P. velledae (Cenomanian) P. forbesianum
3 Phylloceras forbesianuim d'Orb. P. forbesianum (Cenomanian) P. forbesianum
4 Phylloceras minimum n. sp. P. whiteavesi
5 Phylloceras bistriatum n. sp.
6 Vertebrites murdochi n. sp. G. kayei
7 Gaudryceras propemite n. sp. * G. cintum (Pondoland) G. multiplexum (Coniacian) G. multiplenum
8 Gaudryceras particostatum n. sp. G. varicostatum (Pondoland)
9 Gaudryceras subsacya n. sp. G. sacya
10 Gaudryceras politissimum Koss. G. politissimum G. politissimum
11 Tetragonites epigonus Koss T. virgulatus (Pondoland) T. epigonus (Cenomanian) T. epigonus
12 Tetragonites latus n. sp. T. superstes (Pondoland) T. timotheanus
13 Tetragonites simplex n. sp. T. nuperus T. cala
14 Tetragonites margaritatus n. sp. T. sigcau
15 Pseudophyllites indra Forbes Ps. indra Ps. indra Ps. indra
16 Baculites rectus n. sp. (B. vagina)
17 Diplomoceras wakanene n. sp. D. rugatum
18 Ptychoceras zelandicum n. sp. Pt. sipho
19 Acanthoceras ultimum n. sp. Ac. newboldi (Cenomanian) Ac. newboldi
20 Madrasites regularis n. sp. (M. africanus) (M. muravia-turensis)
21 Madrasites multicostatus n. sp. M. buddhaicus
22 Gunnarites antarcticus St. Wel. G. kalika
23 Gunnarites zelandicus Mar. G. kalika
24 Gunnarites inflatus K. & R. G. kalika
25 Gunnarites nordenskjoldi K. & R.
26 Jacobites anderssoni K. & R.
27 Jacobites whangaroaensis n. sp.
28 Jacobites waitapuensis n. sp.
29 Brahmaites rotundus n. sp. Brahmaites sp. Brahmaites brahma
30 Maorites tenuicostatus Mar. ? M. bhavani
31 Maorites densicostatus K. & R. M. aemilianus
32 Maorites suturalis n. sp. M. kaudi
33 Puzosia angusta n. sp. F. compressa (Cenomanian) P. compressa
34 Parapuzosia brevicostata n. sp. P. gaudama (Coniacian) P. gaudama
35 Parapuzosia ordinaria n. sp. P. bhima
36 Tainuia aucklandica n. sp. Ac. vicinale (Cenomanian) Acanthoceras vicinale
37 Parapachydiscus rogeri n. sp. P. aff. wittelkindi P. tweenianus P. tweenianus
38 Hauericeras ngapuhi n. sp. H. gardeni H. gardeni H. gardeni
39 Schluteria rarawa n. sp. S. compactum S. diphylloides
40 Grossouirites gemmatus Huppé §
41 Madrasites haumuriensis Hect. M. bhavani
42 Turrilites circumtaeniatus Koss. T. circumtaeniatus
Number of species in fauna 54 49 53 26 89
Number of allied species in New Zealand 12 5 18 4 11

[Footnote] * Represented in Europe by G. Mite, Lower Senonian.

[Footnote] † Represented in Europe by Ac. rotomagense, Cenomanian.

[Footnote] ‡ Represented in Europe by P. octosulcata, Senonian.

[Footnote] § Recorded by Trechmann, Geol. Mag, dec. 6, vol 4, p. 338, 1917.

[Footnote] ∥ Recorded by Woods, N. Z. Geol. Surv. Pal. Bull. No 4, 1917.

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Forms of the New Zealand Ammonites.
Antarctica, Seymour Island, Snow Hill Island. South Patagonia. Chile (Quiriquina). California. Vancouver. Japan. New Caledonia.
P. nera P. nera (P. surya) 1
P. ramosum P. ramosum P. ramosum P. velledae P. velledae 2
3
P. whiteavèsi 4
P. esoense 5
G. kayei G. kayei G. kayei (Mt. Diablo) G. kayei 6
G. multiplexum? 7
G. tenuiliratum 8
G. sacya G. sacya G. sacya, G. tenuiliratum var. ornatum 9
? Gaudryceras 10
T. epigonus T. epigonus T. aft. epigonus Tetragonites sp. 11
T. timotheanus T. timotheanus T. glabrus 12
13
14
Ps. indra Ps. indra Ps. indra 15
B. chicoensis B. chicoensis ? Baculites 16
? Anisoceras 17
Pt. glaber 18
Ac. turneri (Mt. Diablo) Ac. rotomagense 19
20
? M. cumshewaense ? M. cumshewaense ? M. cumshewaense 21
G. antarcticus 22
G. antarcticus 23
G. inflatus 24
G. nordenskioldi 25
J. anderssoni 26
? J. anderssoni 27
? M. bhavani var. seymouriana 28
? M. bhavani 29
? M. bhavani var. densicostatus 30
31
32
33
? Puzosia sp. P. darwini P. gaudama ? P. gaudama 34
35
Ac. pseudodeverianum 36
P. quiriquinae Pachydiscus sp. P. haradai 37
H. gardeni H. gardeni H. gardeni 38
S. loryi 39
G. gemmatus G. gemmatus 40
41
42
41 20 10 52 27 + 17 47 12
16 2 5 7 2 7 10 4 ?

The following New Zealand species have no representatives in other countries: Gaudryceras crenatum n. sp., Oxybeloceras sp., Madrasites sulcatus n. sp., M. fortior n. sp., Jacobites angularis n. sp., J. minimus n. sp., Neomadrasites nodulosus, Parapachydiscus denticulatus n. sp., Pseudophyllites whangaroaensis. The following additional species have been recorded from New Zealand: (1) by Woods, Gaudryceras sacya Forbes (? G. subsacya), G. baculities cf. vagina (? B. rectus); (2) by Spath (53, p. 299), Tetragonites sp. (? T. simplex), Kossmaticeras bhavani Stol., K. cumshewaense (?Whiteaves) K. & R., K. (Gunnarites) bhavaniforme K. & R.

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Geological Age Of Circum-Pacific Cretaceous Ammonite Horizons.

Whether all these faunas are strictly of the same age may well be doubted. Spath, for instance, says, “The chances then are that a fauna like that of Pondoland which does not quite agree with (e.g.) either the Upper Campanian of Galicia or the Valudayur of southern India, if homogeneous at all, may belong to a hitherto unrecognized horizon or horizons. Since non-sequences are possible, these horizons are, perhaps, not even consecutive” (54, p. 116). Paulcke also, in speaking of the Patagonian ammonites, says, “We find ourselves in this dilemma: Either we have to deal with Lower Senonian strata containing Pachydiscus which shows Upper Senonian characters, or we must suppose that the stratification is wrongly interpreted” (42A, p. 73). Wilckens, who described the lamellibranchs that were collected in the same beds as the ammonites, classes the strata that contain Pachydiscus in the Cenomanian or Turonian age, and thus supports the first alternative. (Lamell. der oberen Kreide Sud-Pat., 1907, p. 60).

Kilian and Reboul, in their work on the ammonites of Seymour Island and Snow Hill, distinguish three different horizons, extending from Cenomanian to the Upper Senonian. Wilckens, however, in his work on the lamellibranchs and gasteropods of the same region, is emphatic that the collections from all of the localities indicate the same age, though he excepts from this statement the localities 2 and 6 of Snow Hill, whence nothing but ammonites was obtained. Wilckens concludes, “Ebenso wie die ubrige molluskan Fauna einheitlich ist. Sie ist obersenonisch. Die Hill Schichten für alter als die alteren Seymour Schichten zu halten liegt kein Grund vor; beide sind obersenonen.”

It is thus apparent that those who have closely examined the faunas from Pondoland, Seymour Island, and Patagonia are at least in grave doubt about their actual age, or, at any rate, differ considerably in their opinions on this question. There is even doubt whether in any locality the strata represent more than one division of the Upper Cretaceous. A tabulated statement of the opinions that have been expressed in regard to the faunas that have been described from the Indo-Pacific countries will make this statement clearer.

[The section below cannot be correctly rendered as it contains complex formatting. See the image of the page for a more accurate rendering.]

Pondoland Upper Campanian-Maestrictian Spath, 54, p. 116.
Upper Santonian van Hoepen, 52, p. 45.
Senonian Woods, 40, p. 345.
Zululand Campanian-Maestrictian Spath, 53, p. 223.
Seymour Island and Snow Hill Cenomanian—Upper Senonian Kilian and Reboul, 46, p. 58.
Upper Senonian Wilckens, 47B, p. 114.
South Patagonia Upper Senonian Paulcke, 42A, pp 72, 73.
Cenomanian—Upper Senonian Wilckens, 39. pp. 57—58.
Quiriquina Upper Senonian Steinmann, 26, p. 27.
Upper Senonian Wilckens, 38, p. 284.
California Upper Chico = Lower Senonian Anderson, 33, p. 62.
Lower Chico = Turonian Anderson, 33, p. 62.
Nanaimo ? Whiteaves.
Lower Senonian Anderson, 33, p. 62.
Japan Cenomanian ? Yokoyama, 17, p. 170.
Middle Cretaceous Jimbo, 22, p. 11.
Diff. Upper Cretaceous divisions Yabe, 37, p. 5.
Senonian Bohm, in Yabe, 37, p. 4.
India—
Aryalur and Valudayur Upper Senonian Kossmat, 28, p. 102.
Trichinopoly Lower Senonian—Upper Turonian Kossmat, 28, p. 102.
Utatur Cenomanian—Lower Turonian Kossmat, 28, p. 102.
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In the general account in his Geology, however, Haug classes all those strata that contain the important fossils Gaudryceras kayei and Pseudo-phyllites indra in the Maestrictian formation. These strata are in general those that have been classed as Senonian or Santonian or Maestrictian by various authors. This point at least is apparent: All those strata that contain the two fossils named above are in all probability of the same age; and, since those authorities that are familiar with the species consider that they are closely related to Gaudryceras planorbiforme and Gaudryceras colloti, it becomes equally certain that this formation is very high in the Cretaceous succession, perhaps even in the Maestrictian. Included in these are the Aryalur, Valudayur, Nanaimo, Lower Chico, Quiriquina, Seymour Island, New Zealand, and Pondoland Upper Cretaceous formations. This has naturally led to wide generalizations, but it is perhaps right to call attention to the present state of our knowledge in regard to the distribution of such animals as ammonites. Information is, of course, meagre and indefinite, as we know nothing of the larval period, the swimming-powers of the animals, or their requirements as regards food or temperature. It appears, however, to be certain that Baculites and Ptychoceras were mud-borers in shallow water, and in this case, unless the larval period was long, they must have required a continuous shore-line with considerable areas of sheltered water in order to have become so widely distributed. Diplomoceras, also, must have had the most limited power of movement on the sea-floor. Species of other genera, such as Pachydiscus, perhaps had habits not very different from those of the present Nautilus, and, given suitable food and temperature-conditions, may have wandered rapidly along a variety of coasts.

There appears to be a general belief that the lytoceratids, in part at least, were stenothermal. Thus Spath speaks of the stenothermal genera Phylloceras and Lytoceras (53, p. 53). He also says that the Pondoland and Zululand faunas are connected by the presence in both of Pseudo-schoenbachia—probably an active swimmer—and of benthonic crawlers and mud-boring Baculites, the stenothermal Lytoceratidae being dependent upon deeper water or warmer currents. The oxycone developments of the Upper Senonian, that might have been thought to be active swimmers, are often curiously restricted, and, like other marine organisms, may have a limited horizontal distribution. He notes, however, that Buckman differs, and thinks that it is wrong to generalize from our knowledge of the habits of Recent forms in regard to extinct groups.

Haug states on this subject, “La presénce du genre Phylloceras et les Lytoceratidae au Japon, dans la Colombie Britannique, en Californie, au Chile, en Patagonie, et dans la Terre de Graham montre avec evidence que l'on n'est pas dans tous ces pays en présence de formations littorales mais qu'il s'agit de formations bathyales, déposées dans un géosynclinal étroit ou s'accumulaient de grandes épaisseurs de dépot” (Haug, Traité de Géologie, p. 1349). He therefore includes much of the area of New Zealand in his “géosynclinal circumpacifique” (p. 1359).

If Baculites and Ptychoceras were mud-borers and Diplomoceras was a benthonic crawler, it is clear that in Upper Cretaceous times the coast-line round the Pacific was nearly continuous, if we are justified in assuming that these genera had a comparatively brief larval period. Since it has already been recorded that species of Baculites showing an Upper Cretaceous character occur in India, Pondoland, Chile, California, British Columbia, New Zealand, and New Caledonia, it is unnecessary to imagine that great swimming-powers were possessed by Phylloceras or the Lytoceratidae in order to account for the presence of species of these genera in the New Zealand fauna of that period.

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The same conclusion is arrived at when the nature of the strata and the fossils embedded in them are considered. The strata certainly give evidence of deposition near a coast-line, for they are often sandy, and sometimes even pebbly and conglomeratic. Fragments of wood and leaves of several species of plants are not uncommon in most of the localities. Such fossils are, of course, most frequently preserved in strata that have been deposited in sheltered waters into which some rivers flow—certainly not in those deposited on an open coast-line nor on the floor of a geosynclinal area. As Phylloceras and species of Lytoceratidae are found in association with them, there is no reason to suppose that the presence of species of those groups is, in this case at least, any evidence of the existence of bathyal conditions in the New Zealand area.

The occurrence of identical or very similar species of Gaudryceras and Phylloceras in countries that now have such different climatic conditions as India, British Columbia, Chile, Patagonia, Seymour Island, and New Zealand, as well as Algeria and western Europe, appears at first sight to support the idea that these genera were stenothermal. However, it is found that closely related species of Puzosids, Pachydiscus, Baculites, Madrasites, &c., have an almost equally wide occurrence, and this term based on such an occurrence would be as applicable to them. It seems perhaps more reasonable to suppose that in Upper Cretaceous times the ammonites as a family were stenothermal, or that climatic zones were far less defined and extreme, and that temperature conditions over the world were far more uniform.

It may be positively stated that none of the formations in which Cretaceous fossils have yet been obtained in New Zealand give any evidence that they have been deposited in any deep synclinorium—even though the formation that in so many localities rests on the fossiliferous rocks of Cretaceous age is a greensand, succeeded by a forminiferal (mainly Globigerina) limestone sometimes siliceous and containing diatoms and radiolaria that may be of deep-water origin. Reasons have been given elsewhere, however, which seem to prove that this limestone is of Eocene age. It is a striking fact that similar material of wide occurrence in New Caledonia has lately been shown to be of Eocene age by A. Heim and A. Jeannet (Bull. Geol. Soc. Geol. de France, 1922, pp. 246—53).

It is noticeable that, with one or two exceptions, such as Baculites chicoensis in California and B. reetus in New Zealand, there is no evidence of a closer relationship of the New Zealand species of ammonites with those of distant lands than with those of nearer countries. In other words, it appears that the New Zealand species are more closely related to those that have been described from countries close to New Zealand than to those more distant, though exception must always be made of Patagonia. This general relation seems to indicate that the circum-Pacific coast-line was much the same in its position in Upper Cretaceous times as it is at the present day. In making this statement, however, it must be borne in mind that the Seymour Island and Chilian coast-lines were certainly not separated from New Zealand by such wide oceanic stretches as now. It is thought by Wilckens that there was a connection between these lands, either continuous or slightly interrupted, a good deal to the north of the present coast-line of the Antarctic Continent. So far as the ammonites of these three countries are concerned, it is almost certain that, though the species found in them are closely similar to those found in India, they are still more closely related to one another. The faunas differ from those of India in the absence of

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species of such general and important genera as Schloenbachia, Scaphites (one species of Scaphites in Quiriquina, Chile), Placenticeras, &c., as well as in having such an unusual development of Madrasites, Jacobites, and Gunnarites.

As to the westward development of New Zealand in Upper Cretaceous times, we have at present no information. Australia seems to have no marine sediments of that age, and it was presumably above the sea-level at that time. Though this, too, was probably the case with the country on the west coast of the South Island of New Zealand, there appears to be no reason to believe that the basin of the Tasman Sea was then a land area, as has been lately suggested by Benson.

The ammonite fauna of Pondoland has been shown by Spath to have some distinct Indo-Pacific characteristics, as well as others of a distinctly Atlantic nature, in the presence of Schloenbachia, Mortoniceras, Sphenodiscus, and Lenticeras. The absence of these important genera in the faunas of Seymour Island and New Zealand seems to me to indicate that South Africa derived its Indo-Pacific elements directly from India along the coast of the western Indian Ocean, and that there was no association with the countries at the south of the Pacific Ocean.

It appears that the New Zealand ammonite fauna of Upper Cretaceous age is of such a nature that it indicates that the general position of the Pacific coast-line was much the same as at the present time. New Zealand was, however, more continuously united with Seymour Island and with India, though we do not at present possess enough information to show us exactly where this coastal connection extended.

Stratigraphical Features of the Batley Series.

The stratification of the Upper Cretaceous rocks of North Auckland is extremely difficult, if not impossible, to unravel with the amount of information at present at my disposal. At Batley there is practically no outcrop of the rock that has not suffered from superficial slipping. The same is true of the occurrence at Whangaroa; and at both of these places the small extent of the fossiliferous beach shows that the actual exposure of the Cretaceous sediments is small. At Bull's Point the stratification is almost vertical, and the thickness of the formation exposed is perhaps 300 ft. Here again, however, surface slipping and soil covering allow very little of the stratification to be seen. In all three localities no fossils have been found actually in situ in the strata. In nearly all cases they have been extracted from concretionary boulders, often of large size, lying on the foreshore. In a few cases only they have been extracted from the boulders by natural agencies, and were lying in the small rock-fragments on the beach.

It has already been stated that much of the fossiliferous rock is sandy or even pebbly, and it is therefore unlikely that the total thickness that is exposed represents much lapse of time. It is not reasonable to suppose that the interval from the Cenomanian to the Maestrictian should be represented by such a small thickness of sediments, which appear to have been deposited rather quickly. It was, of course, hoped and expected that definite species of ammonites would be found to be restricted to certain stratified divisions, and thus make it possible to define exact zones in the stratigraphical sequence. However, as the work proceeded and the collection became more extensive, it was found that no species of ammonites could be regarded as restricted in their occurrence to any particular portion of the beach.

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The question then arose as to whether this apparent mixture of zones could be due to the transport of material along the beach by wave-action. Full consideration of the conditions that actually exist, however, show that wave-transport must be small. If, for instance, the locality of Bull's Point be taken—for in this place the conditions would favour wave-transport more than elsewhere—the following facts must be noted :—

By far the greater number of the specimens were found on the side of the exposure extending west to east for about 100 metres on the north side of Bull's Point. At almost the same spot on the beach were found the following species: Acanthoceras ultimum, Baculites rectus, Gaudryceras subsacya, Gaudryceras particostatum, Gunnarites inflatus, Tainuia aucklandica, Gaudryceras propemite, Maorites tenuicostatus, Phylloceras radiatum, Phylloceras forbesianum, Puzosia angusta, Parapachydiscus rogeri, Nowakites denticulatus, Zelandites murdochi, Pseudophyllites indra, Tetragonites epigonus, Tetragonites latus, Ptychoceras zelandicum.

Several of these species appear to have distinct affinities with species from the Indian Utatur formation, which is, of course, definitely correlated with the Cenomanian. In this respect the following are most important: Tainuia aucklandica, Acanthoceras ultimum, Phylloceras radiatum, Puzosia angusta, Gaudryceras subsacya. Of these the species of Acanthoceras is particularly noticeable; for in the Indian ammonite fauna, which has 167 species, there are twenty-four of Acanthoceras, all of which were found in the Utatur series. It is obvious, therefore, that among the specimens found on the northern side of Bull's Point there is an important Utatur element, and it is certain that if any association of the species named had been found alone it would have been necessary to assign the formation to the Upper Cenomanian age. Associated with these species, however, as is shown in the list given above, there is a very distinct element of the highest ammonite horizon, for Haug has taken the species Pseudophyllites indra and Gaudryceras kayei (of the latter of which Vertebrites murdochi is merely a local representative) as typical of the Maestrictian in all those countries from which they have been recorded. In addition, Diplomoceras wakanene, Ptychoceras zelandicum, and Baculites rectus are indicative of a high horizon. The species of Gunnarites, Madrasites, and Jacobites also belong to an horizon distinctly higher than the Utatur. Thus on the north side of Bull's Point alone species are found that, judging by the Indian succession, would indicate that a great lapse of time is represented by the strata in a very small thickness of rock.

It must be added that a similar association of species has been found in each of the main collecting localities—viz., Bull's Point, Batley, and Whangaroa—though, since the collections made at both of the last two localities are much smaller than that made at the other, the variety of types that has been found is distinctly less. At Batley Pseudophyllites indra, Vertebrites murdochi, Gunnarites inflatus, Maorites tenuicostatus, Baculites rectus, Tetragonites epigonus, Tetragonites latus, Ptychoceras zelandicum, Phylloceras forbesianum, and Gaudryceras subsacya are relatively common. All of these are found at Bull's Point, though Zelandites murdochi was represented by one specimen only. At Whangaroa Vertebrites murdochi and Ptychoceras zelandicum are far more common than elsewhere, and perhaps Hauericeras ngapuhi also. On the other hand, Pseudophyllites indra is less common, as is Baculites rectus. Phylloceras forbesianum occurs, as well as Maorites tenuicostatus. It is thus clear that a similar association of ammonites occurs in each of the localities. The same is true also of the lamellibranchs and gasteropods, though it has not yet been found possible

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to study them fully. Lastly, a species of Araucarites has been found quite commonly at each of the localities, represented by fragments of wood as well as leaves.

Geological Age of the Batley Series.

It is proposed to call this the Batley series, after the locality where these northern New Zealand ammonites were first found. The similarity of the faunas shows that the same horizon or horizons are represented in each of the localities, and it is extremely unlikely that in such a small outcrop as that which is found at Batley and at Whangaroa there should be the same association of higher and lower strata as at Bull's Point, where the outcrop is a good deal larger. It therefore appears to be probable that either the association of species is different from any that has been found in India, or else this New Zealand horizon is intermediate in age between the Utatur and Aryalur horizons of India, but different from the Trichinopoly horizon. Any suggestion of correlation with the Trichinopoly horizon appears to be discounted by the occurrence of such forms as Pseudophyllites indra, Vertebrites murdochi, and Diplomoceras ngapuhi, all of which—or, rather, their local representatives—are restricted to the highest of the Indian ammonite horizons.

If it is agreed that all of these fossils are derived from a small range of horizons, we encounter a great deal of difficulty in correlating the New Zealand formation with equivalents elsewhere. It is necessary to take the Indian series as a guide. The table given on page 194 shows of the fifty-three Aryalur and Valudayur species there are eighteen representatives in New Zealand—that is, a percentage of 34; of the Trichinopoly fauna of twenty-six species there are four representatives, a percentage of 15.5; while of the large Utatur fauna of eighty-nine species there are only eleven representatives, a percentage of only 12.5. It is, then, clear that as regards the Indian ammonites the greatest affinity of this northern New Zealand Cretaceous fauna is with the Aryalur.

The same result may be arrived at in a different manner. If it is admitted that one horizon alone is represented, it is clear that it must contain either Utatur survivals or Aryalur antecedents. Even granting that the isolation of New Zealand was not nearly so extreme in the Upper Cretaceous times as now, it still seems that the former alternative is more probable than the latter.

It is therefore concluded that the Upper Cretaceous rocks of New Zealand are the equivalent of the Aryalur and Valudayur of India. All authorities are agreed in correlating this with a very high horizon in the Cretaceous of Europe. Kossmat takes the Upper Senonian; Spath for probably equivalent formations in Pondoland prefers the Upper Campanian plus Maestrictian, though van Hoepen regards these beds as Santonian. The Upper Senonian, however, is accepted by Kilian and Reboul, and generally by all of those who have described any series of Upper Cretaceous ammonites in the Indian Pacific region. On the other hand, Haug has adopted the Maestrictian equivalent for the Aryalur, and has correlated most of the circum-Pacific ammonite faunas with it. He appears to take as the criterion for this age the occurrence of the species Pseudophyllites indra and Gaudryceras kayei. According to this criterion, the Kaipara and Whangaroa ammonite fauna should be placed in the Maestrictian. My own opinion is that this is rather too high an horizon, and I prefer to take the Upper Santonian or the Lower Campanian as the more probable European equivalent.

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Comparison with other Cretaceous Circum-Pacific Districts.

India.

As a basis for comparison, Kossmat's classification of the Indian formations is taken, and is quoted below. It will be noticed that there are 158 species in the Indian fauna, while there are only fifty-three in New Zealand.

[The section below cannot be correctly rendered as it contains complex formatting. See the image of the page for a more accurate rendering.]

Trichinopoly. Pondicherry.
Danian c. Ninnyur. c. Nerinaea beds.
Upper Senonian Aryalur Group, 53 spp. b. Kulmodu. b. Trigonoarca beds.
a. Otacod, Aryalur, Karapady. a. Anisocei as beds =Valudayur (Blan.)
Lower Senonian b. Upper Trichinopoly.
Turonian Trich. Group, 26 spp. a. Lower Trichinopoly.
c. Cunum beds.
Cenomanian Utatur Group, 89 spp. b. Acanthoceras beds.
a. Muraviatur, Odium, Utatur.
Table showing the Generic Arrangement of Species in India and New Zealand.
Phylloceras. Gaudryceras. Tetragonites. Pseudophyllites. Turrilites Hamites (D'plomoceras, &c.) Baculites. Neoptychites. Placenticeras. Splenodiscus. Ferbesiceras. Schloenbachia. Sch. subgenera. Stoliczkaia. Acanthoceras. Olcostepl anus. Scaphites Holcodiscus Brahmaites. Pachydiscus Desmoceras Puzosia. Hauericeras.
Aryalur 4 3 1 1 0 9 2 0 0 1 0 0 1 0 0 0 2 8 2 11 3 0 2
Trichinopoly 0 2 1 0 1 0 1 0 1 0 0 0 2 0 0 0 4 7 0 5 1 2 0
Utatur 4 8 2 0 6 9 4 2 1 0 2 10 0 4 28 2 3 3 0 1 3 8 0
New Zealand 5 8 4 2 1 3 1 0 0 0 0 0 0 0 1 0 0 12 1 2 1 2 1

In this table Hamites includes Diplomoceras, Ptychoceras, and Oxybeloceras; while Holcodiscus includes Madrasites, Gunnarites, Jacobites, and Maorites, the last for comparative purposes only, without any suggestion as to affinities.

This table shows that the species which have been found in New Zealand belong in general to those genera which in India have a considerable range in time, and actually, with two exceptions, are represented in the formation which is correlated with the Upper Senonian in Europe. The exceptions are found in Pseudophyllites, Turrilites, Puzosia, and Acanthoceras. The only species of Turrilites that has been found in New Zealand came from the Clarence Valley, in the South Island. The two species of Puzosia are perhaps survivals, and this is more remarkable in regard to Acanthoceras ultimum, which is closely related to the well-known Acanthoceras rotomagense.

It is noticeable that twenty-eight species of this genus have been found in the Utatur formation of India. Turrilites also is represented by several species in India. The third of these genera—Puzosia—has species in the Senonian of Pondoland and Chile, the Lower Chico of California, and the Urakawa of Japan.

The species that it is considered do not belong to previously established genera are included in the following new genera: Maorites, probably a development of Dalmasiceras or of Sonneratia, a Hoplitid genus, and

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probably related to some species that have been placed in Puzosia, a Desmoceratid genus; Tainuia, related to Acanthoceras vicinale; and Neomadrasites, derived from Madrasites; also Vertebrites and Zelandites, related to Gaudryceras. In the opinion of the writer these genera indicate a younger rather than an older horizon.

The outstanding features of this ammonite fauna when compared with that of India are most notably the complete absence of Schloenbachia and Scaphites. Another noticeable feature is the abundance of Gunnarites and Jacobites, both of which genera are included under Holcodiscus in the preceding table, which is based on the study of the Indian ammonites by Kossmat. It is also apparent that the genera Phylloceras are Gaudryceras are well represented. If the three species of Maorites are considered as closely related to the genus Puzosia it is clear that it has an unusual representation.

So far as a general statement can be made of the generic features, one is justified in saying that the fauna follows very closely on the main features of the Indian fauna. When the species are compared it is found that there is a considerable number of the Indian species that are extremely close to some in New Zealand. The following species appear to be almost, if not quite, identical: Phylloceras nera, Phylloceras forbesianum, Vertebrites murdochi cf. Gaudryceras kayei, Gaudryceras politissimum, Gaudryceras subsacya, Pseudophyllites indra, Tetragonites epigonum, Hauericeras ngapuhi cf. gardeni, Gunnarites antarcticum cf. Holcodiscus kalika, Brahmaites rotundum, Ptychoceras zelandicum, and Diplomoceras wakanene. This great similarity seems to indicate either that a coast-line was almost continuous from India to New Zealand, or that the species had remarkable powers of dispersion. In connection with this it is well to remember that there seems to be a general agreement that the Phylloceratidae and Lytoceratidae had such free-swimming powers that they were distributed by ocean currents. It is, however, almost impossible that such relatively fixed forms as Baculites and Ptychoceras could have had such means of distribution.

Japan.

This fauna appears to be much less closely related to the ammonite fauna of Japan than to that of India. As in New Zealand, no species of Schoenbachia have as yet been recorded from Japan. Madrasites, however, is not well represented, but species of Jacobites, Gunnarites, and Baculites have not yet been discovered. On the other hand, the species of Phylloceras, Gaudryceras, and Tetragonites show a good deal of resemblance to New Zealand forms, though it may be said that the species of the two last genera, having little ornamentation, have not so much opportunity of displaying striking differences.

The numerous Japanese species of Desmoceras constitute a striking feature, and it seems as though there are no forms in Japan that show analogy with the species of Maorites. The genera Placenticeras, Olcostephanus, Crioceras, and Scaphites, which are absent from the New Zealand fauna, have been found in Japan, as well as a great variety of Turrilites, which, however, come from the lower horizons. The widely distributed species Pseudophyllites indra and Gaudryceras kayei appear to be unrepresented in Japan, while the Gaudryceras sacya of Yokoyama and Jimbo is referred by Yabe to a new species, G. tenuiliratum.

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California.

The Chico formation is well known to include at least one horizon which is universally admitted to be of Senonian age. Anderson's list of the Upper Chico (Lower Senonian) fauna on page 27 includes twelve species of ammonites only. Of these, eight belong to the genera Ancyloceras, Helicoceras, Schloenbachia, and Hoplites, none of which genera are represented in the New Zealand fauna as at present known. Of the remainder, Baculites chicoensis is the only species which shows close relationship to the New Zealand forms. The small number of species does not allow a comparison of any great value to be made. The Lower Chico, however, which is of Turonian age, has a much larger and more representative fauna, and some forty-four species of ammonites are included in it. Among these are twelve species of Schloenbachia and six of Scaphites, which again are genera unknown at present in New Zealand. Of five species only can it be said that there is a definite relationship.

At Mount Diablo there is a fossil-bearing formation, the exact age of which, and relation to the other formations, has not yet been satisfactorily settled. This horizon is of special interest, for it contains Gaudryceras kayei and Acanthoceras turneri, both of which are rather close to New Zealand species of ammonites.

From these statements it would seem that the Californian fauna had certain affinities with the Atlantic fauna that were not shared by New Zealand. Schloenbachia, though so common in Europe and Africa, and extending to India, is nevertheless absent from the Upper Senonian fauna of many circum-Pacific countries. Mortoniceras also is represented in California, though absent from all other Indo-Pacific faunas. (This genus has lately been recorded from Japan.)

British Columbia.

In this country Whiteaves has described two different series of Cretaceous ammonites. The lower of these two formations was found in the Queen Charlotte Islands, and the fossils contained in them are considered by Haug to be indicative of the Albian or the base of the Cenomanian. However, Gaudryceras sacya, Tetragonites timotheanus, and perhaps Hoplites beudanti, show some affinities with members of the New Zealand ammonites. On the other hand, the presence of the genera Schloenbachia, Sphenodiscus, Olcostephanus, and Ancyloceras establish a complete difference from the New Zealand fauna, as well as from that of Seymour Island and of Quiriquina, and perhaps also from that of South Patagonia.

The Nanaimo fauna, however, which is considered by Haug to be of Maestrictian age, and by other authorities to be of Upper Cretaceous age, shows many points of resemblance to the present fauna. The presence of such species as Pseudophyllites indra, Gaudryceras kayei, Baculites chicoensis, Phylloceras velledae, and Hauericeras gardeni at once establishes a relationship that must be regarded as a close one.

Patagonia.

Paulcke has identified twenty species from South Patagonia. These display a considerable difference from those of Seymour Island, Chile, New Zealand, and Japan, especially in the presence of a large series of Hoplites plasticus sp. This series Paulcke himself and Haug compare with North European species, and it thus appears that South Patagonia may have had an Atlantic connection that did not extend to the other

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countries mentioned. The other Patagonian genera are all represented in New Zealand and in other circum-Pacific countries. Pachydiscus and Baculites have four and three species respectively, but Gunnarites and Jacobites, which are common in Seymour Island and New Zealand, have no Patagonian species. Again, there are no species of Puzosia, Hauericeras, or Desmoceras; and it is noticeable that Vertebrites murdochi has no representative species, though it has such a wide Indo-Pacific occurrence.

The species of Hoplites give this fauna a most distinctive character when compared with the other South Pacific ammonite faunas. In other respects, however, all the elements of the fauna might well be found amongst those species that have been found in the north of Auckland.

Chile.

The only locality from which ammonites have been recorded is the island of Quiriquina, in the Bay of Concepcion. Nine species only have been recorded. All the genera, with the exception of Scaphites, are represented in New Zealand. The species that have been recorded show a considerable resemblance to New Zealand species. Though this is a small collection, it seems to show a closer affinity with New Zealand species than that of any other country except Seymour Island.

Seymour Island.

The New Zealand ammonites show rather a close relationship to those described by Kilian and Reboul from Seymour Island, a point to which Kilian has already drawn attention. It is in the genera Madrasites, Gunnarites, Jacobites, and perhaps Maorites, that this is most markedly shown, for these genera have a fuller representation in both countries than in any other. The species of Phylloceras, Gaudryceras, and Tetra-gonites are also rather similar, but perhaps no more so than in the ammonite faunas of the other circum-Pacific countries where Upper Cretaceous ammonites have been described. On the other hand, the absence of Baculites and Ptcychoceras, especially the former, is rather surprising. On the whole, as previously remarked and as shown in the tables on previous pages, the Seymour Island fauna is more closely related to New Zealand than that of any other country.

Fossils Found With The Ammonites.

Remains of a large number of organisms have been found in association with the ammonites.

The plant-remains are described by Mr. W. N. Edwards in the present volume (pages 121128).

An echinoid was sent to Dr. Bather; he forwarded it to Professor Hawkins, who was good enough to examine it, and he remarks that it is probably a true Hemiaster.

Dr. Smith Woodward was good enough to examine the fish-scales, and detected some that were characteristic of Cladocyclus, a fish of the Cretaceous family Ichthyodectidae.

Two species of brachiopods were sent to Dr. J. A. Thomson, who forwarded them to England, but no report has yet been received.

There are about twelve species of gasteropods, which include a form close to Amberleya spinigera Wilckens, from Seymour Island.

The lamellibranchs include a species of Thyasira close to T. townsendi Wilckins, from Seymour Island. It is hoped to classify the species of gasteropods and lamellibranchs next year.

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