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Volume 61, 1930
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New Shells from New Zealand Tertiary Beds.
Part 3.

[Issued separately, 29th May, 1930.]

Plates 1-6.

Barbatia awamoana n. sp. (Figs. 63, 64, 65).

This is the Awamoan (Miocene) representative of the Recent novaezelandiae Smith, and its direct ancestor. It is markedly more elongate and not so high, the anterior end is fairly regularly convex instead of rather squarely truncate, and the internal grooves are not so prominent. I am unable to observe any other differences, but as these are quite constant, it would be misleading to report novaezelandiae from the Awamoan.

Length, 51.5 mm.; height, 28 mm.; diameter (1 valve), 11 mm. Corresponding dimensions for a Castlecliff shell, 48 × 28 × 11 mm.

Locality—Target Gully, shell-bed (Awamoan), type and numerous other specimens; also Awamoa beach-boulders.

Type in Finlay collection.

Cosa wanganuica n. sp. (Figs. 75, 76, 77).

Very close to trigonopsis (Hutt.), and intermediate between that species and filholi (Bernard), but nearer the former. Differs at sight in having the anterior side straight, while in trigonopsis it is concave and excavated; this gives the latter species a more slender and sharply beaked aspect. The concentric riblets are slightly finer, and the prodissoconch somewhat larger. The radial ribs are slightly more numerous, 16-17 as against 13-14 in trigonopsis. Otherwise in the general shape and the narrow umbos the new species is more allied to the Nukumaruan species than to filholi.

Height, 3.8 mm.; breadth, 3.3 mm.; thickness (1 valve), 1.2 mm.

Locality—Castlecliff “papa” (Castlecliffian), very common in certain patches, especially where there are the remains of a tree-coral or bryozoan, but otherwise rare.

Type in Finlay collection.

This species has always been mistaken for trigonopsis, but the latter is apparently limited to the Nukumaruan.

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Cosa trigonopsis (Hutton).

  • 1885. Mytilicardia trigonopsis Hutton, Trans. N.Z. Inst., vol. 17, p. 324.

  • 1893. Mytilicardia trigonopsis Hutton, Macleay Mem. Vol., Plioc. Moll., p. 85; Pl. 9, F. 94.

  • 1898. Philobrya trigonopsis (Hutt.): Tate, Trans. Roy. Soc. S.A., vol. 22, p. 87.

  • 1915. Philobrya trigonopsis (Hutt.): Suter, N.Z. Geol. Surv. Pal. Bull. No. 3, p. 50.

Suter's drawing in the Macleay Memorial Volume is quite a good representation, but the specimen was evidently worn. Nukumaru shells agree exactly with Petane ones in shape and number of ribs.

Cosa filholi (Bernard, 1897). (Figs. 78, 79, 80).

(This Recent species is discussed here for convenience).

Iredale has expressed the opinion (Proc. Mal. Soc., vol. 9, p. 75, 1910), as noted by Suter (Man. Moll., p. 1083), that this is the young stage of Philobrya costata Bernard. Suter at the same place gives corrected dimensions and affirms that there are two species. He is perfectly correct. I have sorted out the two forms described by Suter as costata and filholi from many different dredgings in the Cookian, Forsterian, and Rossian provinces. Filholi is rather commoner in the north, costata in the south; both species, but especially the latter, are very common in 60 fathoms off Otago Heads.

Suter's description of the number of ribs in each species is erroneous; it is rather difficult to count the ribs exactly, as they become so fine and weak near the dorsal margins, but there are usually about 13 in costata and 15 in filholi. The latter, however, can always be separated by the character of the ribs, which are triplicate, the centre portion being carinate and high, the side pieces thread-like and low, the whole forming a sharp triangular ridge, with a triangular projection at the margin; in costata the ribs are single, stout, and raised, flattish on top, with a median linear groove, forming a squarish projection at the margin. The interstices in filholi are wide, shallow, and flat, twice the width of the ribs or more at the margins; in costata they are narrow, deep, slightly concave, equal to or less than the ribs at the margins. There are also marked differences in the outline of the shells, filholi being constantly less vertically elongate, more squarish, more inflated, the anterior margin slightly convex instead of straight and excavated, etc. The surface of filholi has a curious waxy sheen, absent in costata. The two species are thus amply distinct.

Whether filholi of Suter's “Manual” is really filholi Bernard, however, is another matter. The original description and figures are not available to me, but, pending their re-examination in the light of the comparative notes given above, I think Suter's determinations may be taken as correct. If filholi Bernard should turn out to be really based on a juvenile costata, a new name will be needed for the quite distinct filholi auct.

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Of the two species, filholi has the longer ancestry, as known at present. Suter (Man. Moll., p. 858) says of costata that “The Pliocene P. trigonopsis Hutton (Mytilicardia) is very nearly allied, but the riblets are finer and more distant, and they are lacking the median groove,” and again (N.Z. Geol. Surv. Pal. Bull. No. 3, p. 50, 1915) of trigonopsis that “This species is allied to P. costata Bernard, but it is much larger; the prodissoconch is indistinct and convex; the costae are not grooved, but keeled, and the concentric threads are not wavy but straight.” But these are the very characters that approach trigonopsis to filholi, to which, not to costata, it is the ancestor. It is very like costata in shape, being more vertically elongate than filholi, and not having a convex anterior side, but there is the same tendency to flatten and form sharp angles at the basal corners as in filholi, and the sculpture at once shows the alliance. Probably the initial error is due to Tate, who at the reference given under trigonopsis stated, “The above amended generic reference is based on the study of co-types kindly transmitted to me by the author of the species. It closely resembles P. costata, but which [sic] has thicker and closer ribs.” He also states that he received specimens of costata from Bernard; it seems improbable that the author of filholi would confuse the two species, so we can only conclude that for once Tate's usually accurate perception was at fault.

I have seen no Tertiary representatives of costata; over 100 shells from Castlecliff were all wanganuica.

Apart from the shape, trigonopsis and wanganuica differ from filholi principally in having the ribs rather wider and closer (interstices little more than their own width), projecting further at margins, the keel serrated with sharp spikes instead of almost smooth, and the concentric ribs in the interstices not cords with narrower grooves between, but thread-like, with wide interstices.

I have elsewhere shown (Trans. N.Z. Inst., vol. 57, p. 448, 1926) that Hochstetteria Velain, 1878, should replace Philobrya auct., not of Carpenter, 1872, for the meleagrina series in New Zealand (Philippiella Pfeffer, 1887, being a synonym), and proposed the genus Cosa for the costata series. This should include, besides the four Neozelanic members mentioned, several undescribed Tertiary species, and the following Australian members: (Recent), fimbriata Tate, 1898 (Trans. Roy. Soc. S.A., vol. 22, p. 87), tatei Hedley, 1901 (Rec. Austr. Mus., vol. 4, p. 24), pectinata Hedley, 1902 (Mem. Austr. Mus., No. 4, p. 229), and parallellogramma Hedley, 1906 (Proc. Linn. Soc. N.S.W., vol. 29, p. 544); (Tertiary), bernardi Tate, 1898 (Trans. Roy. Soc. S.A., vol. 22, p. 88), and praenuntia Tate, 1898 (idem.).

Notovola tainui n. sp. (Figs. 46, 56, 81).

Shell close to novaezelandiae (Reeve), but more inflated, especially towards the ventral margin, and more laterally expanded (less circular). Right (convex) valve with ribs same in number and arrangement, and with the same faint radial lineations and scratches on their surface; but the ribs are broader, flatter on top, with sharp edges, and the interstices are very much deeper, giving the appearance of deep channels scored across the surface instead of more or

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less rounded furrows. This is especially noticeable towards anterior side. The interior shows 14-15 strong square-cut ridges separated by interstices 1½-2 times their width; in the Recent species there are 16-18 ridges with interstices 1-1½ times their width. On the left valve there are about 14 very strong and high ribs (mostly higher than broad), evenly rounded on top, with interstices 2-3 times their width; novaezelandiae (Fig. 82) has about 16 considerably weaker ribs (broader than high), flattened on top, with interstices 3-4 times their width. The left valve is noticeably concave, while its Recent descendant has a mostly flat valve, concave only beneath the umbos. Interstices and sides of ribs on both valves, but especially the right, are densely ornamented with fine raised lamellae, equi-distant and several times their width apart; these are not noticeable in the Recent species.

Height, 88 mm.; width, 100 mm.; thickness (1 valve), 29 mm. (type).

Height, 109 mm.; width, 115 mm.; thickness (1 valve,) 29 mm. (paratype).

Locality—Castlecliff “papa” (Castlecliffian).

Type and one paratype, in Finlay collection.

“Tainui” was the name of one of the first Maori canoes to reach New Zealand. If, as seems probable, this Castlecliff shell is the first migrant of this group of Pecten from Australia (or the north) to our shores, the specific name is not inept.

Notovola marwicki n. sp.

This differs from all the others of this group in its subobsolete sculpture on the concave valve. Instead of prominent raised ribs with more or less deeply excavated wide interstices as in fumatus, olbus, meridionalis, novaezelandiae, and tainui, this species has low, lightly convex (almost flattish) ribs, with merely narrow indentations (almost sublinear grooves) between. The ribs flatten and widen still more towards ventral margin, and the interstices become wider and less definite so that near the edge the sculpture is merely a series of undulations. In shape, convexity, and interior, the right valve is practically identical with the South Australian albus Tate, but the beak is markedly broader. The left valve is also practically inseparable from albus, but the ribs are slightly broader, and the valve definitely concave. This also separates it from novaezelandiae, whose ribs on this valve are also higher and rounder. The laminae so prominent in the interstices of tainui are absent on the right valve of marwicki, but present on the flat valve, where however they are at least three to four times as numerous; densely packed, their own width or less apart, imparting a curious roughened surface to the shell.

Height, 65 mm.; width, 72 mm.; thickness (1 valve), 22 mm.

Locality—Castlecliff “papa” (Castlecliffian), apparently rare.

Type in Finlay collection, one other specimen in N.Z. Geol. Survey collection.

The Sydney (Peronian) form N. fumatus (Reeve) approaches nearest to marwicki in rounding and weakening of ribs and interstices

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on right walve, but it has such high and strong beaks and so convex and characteristically shaped a shell that relationship does not seem very close. The only Recent New Zealand species, novaezelandiae (Reeve), seems in some ways intermediate between tainui and marwicki, as if they had combined to produce it; both the Pliocene forms carry various sculptural features to excess, though in different ways.

Gari oamarutica n. sp.

Very close and directly ancestral to the Recent lineolata (Gray), but relatively more elongate and narrower. The greatest difference is seen in the anterior end, which is much more acuminate, the dorsal margin being straight instead of lightly convex, and much more narrowly convex on meeting the basal margin. No other differences observable.

Length, 30.5 mm.; height, 14.5 mm.

Locality—Awamoa beach-boulders (Awamoan), type and several fragmentary specimens. Also Target Gully shell-bed (numerous broken shells), Otiake, and other Awamoan and Hutchinsonian localities.

Type in Finlay collection.

Maorimactra acuminella n. sp.

Close and directly ancestral to the Recent M. ordinaria (Smith), but more inequilateral, the anterior side less produced, the posterior side more produced and much sharper. Shell higher, more inflated, posterior dorsal carina better marked, anterior one weaker. Pallial sinus truncated instead of squarely rounded.

Length, 15 mm.; height, 12 mm.; thickness (1 valve), 3.5 mm.

Locality—White Rock River shell-bed (Awamoan), type and several more beautifully preserved valves; also Nukumaru (Nukumaruan), and Castlecliff (Castlecliffian).

Type in Finlay collection.

This species has a range from Miocene (perhaps earlier) to top-most Pliocene, but alters in the Recent fauna. It is highly exceptional in that the Castlecliff forms agree not with the living ones but with the Awamoan ones.

Scalpomactra continua n. sp.

Very close and directly ancestral to the Pliocene and Recent S. scalpellum (Reeve), but differing at sight in its longer lateral teeth, especially posteriorly. It also has a better marked posterior dorsal keel, and consequently a sharper posterior end; the shell is slightly more elongate and has a deeper pallial sinus.

Length, 24 mm.; height, 14 mm.; width (1 valve), 3.5 mm.

Locality—White Rock River shell-bed (Awamoan), type and numerous specimens. Also Target Gully, Pukeuri, Awamoa, Chatton, Wakaia, etc.

Type in Finlay collection.

This will be the species Dr. Marwick has recorded from Chatton with the remark (Trans. N.Z. Inst., vol. 59, p. 906, 1929), “The

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Recent species Scalpomactra scalpellum is doubtful. More specimens are required to show whether they are to be separated as a distinct species of not.”

Scalpomactra biconvexa Powell and Bartrum (Trans. N.Z. Inst., vol. 60, p. 405; F. 108) from Oneroa, Waiheke Is., is still more elongate and apparently has more convex dorsal margins; the hinge is stated to be as in scalpellum.

The description of the last three new species removes three more records of Recent species from the Awamoan fauna. Extremely few of the “Miocene” species regarded by Suter as representing living forms are really inseparable from Recent shells when carefully compared. When the Awamoan fauna has been thoroughly revised it is to be expected that the percentage of Recent species will be very low—probably under 5 per cent.

Scutus petrafixus n. sp. (Fig. 23).

Shell ancestral to the Recent S. breviculus Blainv., but differing at sight in its proportions. It is considerably less elongate and relatively wider; it appears to be a trifle wider in front than behind, whereas breviculus narrows anteriorly. The hinder end, as far as can be seen, seems to be regularly convex instead of squarely truncate, and there is no indication in the growth lines of the notch that is well marked in breviculus.

Length, 50 mm.; width, 33.5 mm. Corresponding dimensions for breviculus—60 × 34.5 mm.

Locality—Oamaru limestone (Ototaran).

Type in Finlay collection.

The exact locality of the single specimen is unknown, but it is certainly from an Oamaru collection, and the matrix is hard, finegrained limestone, slightly glauconitic. The specimen is possibly somewhat compressed, but does not appear much distorted. In spite of these deficiencies, the genus is so rare in the Tertiary that it is worth recording, if only to show that breviculus had a long Neozelanic ancestry, and is not of recent importation.

Crosseola proerrata n. sp. (Figs. 11, 12).

Ancestral to the Recent C. errata Finlay (Trans. N.Z. Inst., vol. 57, p. 402, F. 33; 1926), from which it differs in smaller size, more depressed shell, and greater prominence of the axials. Apex of one smooth flatly bulbous whorl. As in the Recent species, there are 3 subequal spirals on spire whorls, a fourth showing just at lower suture; 8 rather low and weak spirals, twice their width apart on body whorl; 6 of these stronger. Axials about same in number as in Recent shell, but much heavier and blunter, altogether over-riding spirals instead of strongest between them. Basal fasciolar cord not nearly so strong and projecting as in errata, the base consequently flatter. As in that species, the aperture is perfectly circular and unnotched, with only a pad at the fasciole, thus differing from the Australian cancellata.

Height, 1.4 mm.; diameter, 1.4 mm.

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Locality—Target Gully shell-bed (Awamoan), two examples. Also one specimen with slightly stronger basal keels from Clifden, band 6B (Hutchinsonian). From Pourakino, Riverton, I have also a single specimen which probably represents a distinct species, the shell being very depressed and the basal keels very strong; it seems to be adult, but I prefer not to give it a name till more material is available.

Type in Finlay collection.

Crosseola sultan n. sp. (Fig. 6).

Shell large for the genus, prominently 5-keeled. Apex small, globose and smooth, of one sub-helicoid whorl, the tip slightly bulbous. Four succeeding whorls, the first two with 2 spirals (1 on keel and 1 below), next with a third smaller one arising out of suture below, body whorl with 5 strong sharp much raised keels (equidistant and twice their width apart), and a stout fasciolar cord as strong as the keels but blunter. Shoulder area twice the width of interstices between keels, with no spiral sculpture, but a convex medial bulge. Radial riblets very dense fine and flexuous, interstices 1-2 times as wide; they extend from suture to fasciolar cord, practically absent on outer edge of keels, prominent in interstices; on upper and under surface of spiral keels the axials are very sharp and fine, and 2-3 extra lamellae are intercalated between them, the axial scullture thus appearing there several times as dense. Spire lower than aperture, suture slightly canaliculate. Aperture large, circular. Outer lip with 5 sharp triangular serrations, the sudden terminations of the keels. No basal notch, but aperture slightly channelled along fasciole pad. Inner lip weakly callous and a little reflected. Umbilical chink weak.

Height, 4 mm.; diameter, 3 mm.

Locality—Target Gully shell-bed (Awamoan); one example.

Type in Finlay collection.

This fine species—apparently the largest of the genus—is also an ancestral form, being nearly related to the Recent C. cuvieriana (Mestayer) (Trans. N.Z. Inst., vol. 51, p. 132, 1919). That species is also strongly 5-keeled, and shows the sudden dense lamination on the sides of the keels. It differs at sight, however, in the spacing of the sculpture, the axials being less numerous, and 3-4 times their width apart, and the spiral keels being unevenly distributed, a gap almost as wide as the shoulder between the upper peripheral pair, the rest close together on base.

Dolicrossea awamoana n. sp. (Fig. 10).

Shell ancestral to, and very like, the Recent D. vesca Finlay (Trans. N.Z. Inst., vol. 57, p. 403, F. 32; 1926), but less globose, and with a strong basal notch. The spiral grooves are about twice as numerous, the outer lip more thickened, and the fasciolar cord much more projecting, carinating the base and interrupting the peristome (which is almost continuous in vesca) with a strong canal-like notch.

Height, 2.7 mm.; diameter, 2 mm.

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Locality—Awamoa blue clays (Awamoan), one specimen. Also one damaged shell from Clifden, 6B (Hutchinsonian) which appears inseparable at present.

Type in Finlay collection.

Dolicrossea clifdenensis n. sp. (Fig. 25, 26).

Like the previous species, but spire more exsert, a more pronounced tabulation below suture, spiral lirae coarser on early whorls and obsolete on body whorl, a still stronger and more twisted fasciole cord, slightly deeper and narrower notch, and a more excavated piller.

Height, 2.5 mm.; diameter, 1.7 mm.

Locality—Clifden, 6c (Hutchinsonian), several specimens.

Type in Finlay collection.

Argalista proumbilicata n. sp. (Figs. 20, 21, 22).

Small, depressed-turbinate, umbilicate. Spire low, whorls about 3½, including protoconch, convex, base flattened. Embryo smooth, next half whorl with three strong ridges, the median one prominently raised; these die away rather suddenly and leave the upper surface of the shell rather smooth except for a few spiral grooves, three fairly close near suture, one rather distant, then usually a smooth space down to periphery (but this may bear two or more grooves); below this there are numerous much closer spiral grooves down to umbilicus, getting wider apart as they near it, about 14 altogether up to middle line of periphery. Suture impressed and margined by a slight swelling. Aperture circular, somewhat effuse at pad; outer lip thin. Umbilicus deep, open but not wide, surrounded by a heavy coarsely crenulated margin that eventually forms the prominent pad at base of pillar.

Height, 1.7 mm.; width, 2.5 mm.

Locality—Target Gully shell-bed (Awamoan), type and numerous other examples.

Type in Finlay collection.

This species, effusa Marwick, and umbilicata Powell, are distinguished from the fluctuata line by the more widely open umbilicus. The present species is specially distinguished by its heavily crenulated umbilical edge and post-embryonic ridges; from effusa it also differs in other details of spiral sculpture and depressed shell, while the Recent umbilicata has a still more open umbilicus, effuse aperture, and weaker pad.

Argalista kaiparaensis n. sp.

Similar to proumbilicata, but much smaller, no post-embryonic sculpture of ridges; upper surface evenly and rather prominently grooved, with quite a stout cord margining suture, lower surface finely grooved; the same very coarsely crenulated margin to the umbilicus; pad sub-triangular instead of semi-circular.

Height, 1.0 mm.; width, 1.4 mm.

Locality—Pakaurangi Point, Kaipara (Hutchinsonian).

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Type in Finlay collection.

This is easily the smallest species of the genus; the state of the umbilicus, pad, and aperture shows that it is fully adult.

Argalista impervia n. sp.

Shell small, turbinate, not depressed, imperforate. Spire rather raised for the genus, whorls four including protoconch, convex, base flattened, last whorl descending. Sculpture of spirals only, post-embryonic half whorl with ornament somewhat similar to proumbilicata, but the two outer ridges much feebler, giving the whorl merely a carinate appearance; suture very narrowly but distinctly margined, a few close grooves near suture, rest of upper surface practically smooth and shining; below periphery very dense and numerous fine spiral grooves, regular and equidistant, but fading out before reaching centre; a smooth calloused surface surrounds the umbilical depression, sometimes with a few irregular crenulations. Aperture circular, not effuse, outer lip thin and sharp, but rapidly becoming very thick inside. Columella concave, calloused, somewhat excavated or sunken at the umbilical area, umbilicus absent or limited to a pinprick depression. Pad very tiny.

Height, 2.3 mm.; width, 2.9 mm.

Locality—Target Gully shell-bed (Awamoan), common. Not seen from any other locality.

Type in Finlay collection.

This was always taken by Suter for fluctuata (Hutt.); it may be ancestral to it, but differs at sight in its entirely closed umbilicus, higher and more solid shell, less expanded and more descending last whorl, and weaker sculpture on upper surface. A. arta Marwick, from the Chathams, is much more depressed (but either his figure or his dimensions are quite wrong—I am basing comparison on the figure) and has prominent spiral sculpture all over.

Badenia zebina n. sp.

(Badenia is a substitute name for Powellia Finlay, preoccupied—see elsewhere in this volume).

Shell minute, the smallest of the genus, short and rather squat. Embryo indistinct, of about one whorl, smooth, compact, not marked off from the shell whorls, of which there are about three. Whorls convex, bulging at lower third, smooth and shining; here and there for short distances extremely obscure indications of a few thread-like keels appear. A very blunt and low subangulation closely encircles the narrow but distinct chink-like umbilicus. Aperture as in B. lactea (Finlay), the type of the genus, but relatively much smaller, the walls solid, more outwardly effuse but less channelled below, more backwardly inclined above, the varix behind the edge heavy. Spire about one and a third times aperture in height.

Height, 1.9 mm.; diameter, 1.2 mm.

Locality—Otiake, sandy beds above limestone (Upper Ototaran), 14 examples.

Type in Finlay collection.

Like lactea in whorling, but much smaller, and with a much shorter spire. Somewhat like a minute Zebina in general appearance.

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Rissopsis castlecliffensis n. sp.

Shell small, cylindrical, with weak axial and obscure spiral sculpture. Embryo well-developed, of nearly two whorls, beginning in a blunt and flattened point, ending in a weak varix. Three and a-half succeeding shell whorls, lightly convex, the sutures well marked, very faintly submargined below. Weak and irregular axial ribs (less or more than own width apart in different places) on spire whorls, obsolete on body whorl, these are frequently worn off altogether. Obscure indications here and there of spiral lirations. Spire 2½ times height of aperture, which is small, pressed to body whorl, subcontinuous, peristome thin and sharp, without a varix, half hiding the tiny umbilical chink, somewhat effuse below.

Height, 2.3 mm.; diameter, 1.0 mm. (type).

Height, 2.7 mm.; diameter, 1.2 mm. (worn paratype).

Locality—Castlecliff “papa” beds (Castlecliffian), 6 examples.

Type in Finlay collection.

Generically located with some doubt; I have seen no authentic examples of the genus, but the aperture and general habit are reminiscent of Australian shells placed here. If correct, it is the first record of this genus from New Zealand.

Rissopsis fricta n. sp.

Differs from the previous species only in much smaller size, slightly more convex whorls, a little more tightly clasping at suture, and more effuse aperture anteriorly.

Height, 1.8 mm.; diameter, 0.7 mm.

Locality—Target Gully shell-bed (Awamoan), 5 examples, the adults all worn.

Type in Finlay collection.

Magnatica fons n. sp. (Fig. 51).

Ancestral to M. planispira (Sut.). Shell smaller, and with a decidedly higher and more pointed spire, much more the shape of M. altior Finlay. The umbilical characters, however, show that it belongs to Magnatica s. str., not to section Spelaenacca. Umbilicus narrow, not cylindrical, with no internal groove, but a narrow thread some distance from the main funicle, which is feeble and indistinct, close to upper callus. A rather sharp ridge winds round just outside umbilicus and enters it just below parietal callus pad; this ridge is similar to the angulation in planispira but is sharper.

Height, 22.5 mm.; diameter, 21 mm.

Locality—Waihao Downs (Bortonian).

Type in Finlay collection.

This is the earliest Magnatica. The separation of the Spelaenacca group was also quite ancient, as shown by the occurrence of a true Spelaenacca (the following species) in the McCulloughs Bridge greensand.

Magnatica (Spelaenacca) parilis n. sp.

Extremely similar and certainly ancestral to altior Finlay. Only one somewhat crushed specimen is at present available, but this dif-

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fers in more rounded spire, less spreading parietal callus, steeper posterior channel to the aperture, considerably wider and more open umbilicus, still deeper groove within umbilicus and stronger carina below it, and better developed funicle, which is well separated from parietal wall.

Height, about 33 mm.; true width uncertain.

Locality—McCulloughs Bridge greensand, just below limestone (Tahuian).

Type in Finlay collection.

The section Spelaenacca has a deep groove within the umbilicus, bounded by a ridge below; it is more a sudden step down than anything else, like an escarpment in geology. Magnatica has merely a thin distant thread-ridge, with no step down; a less pervious umbilicus, somewhat flattened from one side, and a stronger angulation bounding the umbilicus. I think my Magnatica (Spelaenacca) altior (Trans. N.Z. Inst., vol. 56, p. 228; Pl. 60, Figs. 3, 4; 1926) should be reduced to a synonym of Natica (Magnatica) sutherlandi Marwick (l.c., vol. 55, p. 555; Pl. 56, F. 1; 1924); my only specimen of the latter is somewhat worn, but there are no essential differences, and the horizons are the same. I overlooked comparison with this species when I described altior. This will leave the species of Magnatica as fons Finlay, approximata (Suter), planisipra (Suter), and nuda Marwick, while Spelaenacca contains parilis Finlay, sutherlandi (Marwick) (= altior Finlay), clifdenensis Finlay, and rectilatera Finlay.

Cabestana debilior n. sp. (Fig. 31).

Very close to the Recent C. waterhousei Ad. & Ang., but more slender, with a longer beak. Spirals have exactly the same arrangement, but the main ones (more especially above base) are weaker, and the interstitial ones stronger. Axials much weaker, merely thin ridges, many times their width apart, extending from suture to suture, instead of stout ribs much more prominent on periphery and 1½–2 times their width apart. Intersections with peripheral spirals produced into tiny rather sharp nodules instead of prominent tubercles. Waterhousei has four intervariceal subequidistant ribs till the penultimate whorl, on that and on body whorl there are five, the last weaker; debilior has four on all whorls, the first becoming very weak on last two whorls, very unequally spaced, the first near varix, the next three subequidistant, then a wide space before next varix with no axial ribs. Sutures more cut in.

Height, 53 mm.; of spire, 22.5 mm.; width, 27 mm.

Locality—Castlecliff “papa” (Castlecliffian).

Type in Finlay collection.

Iredale (Trans. N.Z. Inst., vol. 47, p. 460; 1915) noted that waterhousei had not been observed in New Zealand, and was a distinct species from spengleri. Since then Powell (l.c., vol. 57, p. 560; Pl. 33, F. 2; 1927) has recorded and figured a living specimen obtained by La Roche at Parengarenga. His figure does not exactly agree with a topotype I have, and in view of the presence in New Zealand of this ancestral Castlecliff species, his shell may possibly be

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distinct from South Australian specimens. More specimens are needed to settle this point; it is evidently yet another of the Australian Cymatiidae which ocean currents have borne across to us—whether in Pliocene or Recent times one cannot yet say.

Iredale (Rec. Austr. Mus., vol. 17, No. 4, p. 177; Pl. 41, F. 2; 1929) has recently separated the New South Wales Recent form from the typical South Australian waterhousei as a subspecies frigidulum, and this is very close indeed to debilior, but is apparently still more slender and has the axial sculpture relatively weaker in proportion to the spiral. Powell and Bartrum (Trans. N.Z. Inst., vol. 60, p. 425; F. 87, 88; 1929) have described Cymatium tetleyi from Waiheke Is. as probably ancestral to waterhouse, but the resemblance in this case is much less close, and a different group seems to be represented.

Pleia n. gen.

A group of the Fasciolariidae, differing from Pleuroploca Fischer chiefly in having only one weak plait on the pillar instead of three. Pleuroploca has the twist of the pillar marked by a strong ridge, with two more separated by deep furrows above it; Pleia has no ridge at the twist, but a single not strong plait above it, the columella not excavated on either side of it. The shell habit is taller and more slender than Pleuroploca; there are strong coarse axial ribs and spiral cords; embryo large, paucispiral, the top flattened and blunt.

Type: Fasciolaria decipiens Tate, 1888.

The genotype is from the Australian Balcombian (Oligocene?). Tate says there are “two oblique plaits hardly visible from without,” but this is a mistake; even grinding away the upper whorls shows no more than a single weak plication.

Pleia otaioensis n. sp. (Fig. 30).

Shell rather narrow and slender, with crude axials and bold narrow spirals. Protoconch rather large, of two (?) whorls, the tip somewhat flattened, the next whorl a little bulbous, following 2-3 whorls worn so that junction of apex and shell cannot be seen. Nine whorls including apex; fairly regularly convex, subshouldered at upper third, the shoulder steeply sloping and straight, the shoulder angle very bluntly rounded, thence sloping inwards in a light curve to lower suture. Sutures inconspicuous, submargined by a narrow thread below. Axials 9 per whorl, thick and prominent, bluntly rounded, their summits about own width apart, but bases swelling to meet each other, and hardly separated; ribs weak on shoulder, just reaching upper suture, thickest medially, a little weaker at and undulating the lower suture, rapidly disappearing below suture on base, the lower part of which and the canal are free from axials. Five equal and strong spiral cords run over ribs and interstices between shoulder angle and lower suture, with four more weaker ones on shoulder, and numerous progressively weaker ones on base and canal below main five, which have wider interspaces (twice their own width) than others. Outer lip heavily crenulated by internal ribs arranged in pairs which meet internally in sharp angles. Parietal wall with a prominent callus tubercle forming a marked channel with

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outer lip. Inner lip smooth, well limited. Columella fairly straight, twisted a little at inception of canal, with a single inconspicuous plait and a weak groove above it, a little above this twist. Canal long, open, slightly bent to left, longer than aperture (but broken off).

Height, 34 mm.; of spire, 16 mm.; of aperture, about 10 mm.; diameter, 10.5 mm.

Locality—Blue Cliffs, Otaio River, sandstone above limestone (Upper Ototaran?)

Type in Finlay collection.

This is what Suter identified (Alph. List N.Z. Tert. Moll., p. 14, 1918, and N.Z. Geol. Surv. Pal. Bull. No. 8, p. 62, 1921) as Fasciolaria johnstoni. But Fusus johnstoni Ten.-Woods, 1877 (Proc. Roy. Soc. Tas. for 1876, p. 94), figured by Tate (Trans. Roy. Soc. S.A., vol. 10, p. 136; Pl. 12, F. 4a, b; 1888), and represented by authentic topotypes in my collection, is a rather thin shell with very regular spiral ornament, a sharply keeled periphery on the body whorl, a straighter canal, and an exceedingly small paucispiral embryo; it has a weak plait on the pillar, but seems not distantly related to true Colus, while the New Zealand shell appears to be much closer to Fasciolaria decipiens Tate (l.c., p. 150; Pl. 8, F. 1), especially the tall-spired Muddy Creek form. The details of aperture, pillar, and embryo seem to be identical, but otaioensis is a smaller shell, more regularly ornamented. As these shells are quite unlike the Recent tropical Murex trapezium L., the genotype of Pleuroploca Fischer, a new group Pleia has been made for them. I have thought it better in this case to make an Australian shell the type, as decipiens is common, while otaioensis is known to me from but a single specimen, though probably further members of the group will turn up in New Zealand. Possibly Fasciolaria concinna Tate also belongs to this group, but tenisoni T.-W., cryptoploca Tate, cristata Tate, and rugata Tate are all much closer to Pleuroploca. Iredale (Proc. Linn. Soc. N.S.W., vol. 49, pt. 3, p. 265; Oct. 24, 1924) has located the Recent Sydney forms in Pleuroploca, but remarks that “All the Australian radulae agree in showing fewer cusps on the laterals than the typical Fasciolaria or Pleuroploca,” and that “there is a fossil Fasciolaria decipiens, a form not unlike bakeri, showing the plications very obscurely.” I have not seen bakeri Gat. & Gab., but as it is generally treated as a subspecies of australasia Perry, it is probably nearer to Pleuroploca than to Pleia.

Proximitra apicalis (Hutton). (Figs. 68, 72, 73).

  • 1873. Mitra apicalis Hutton, Cat. Tert. Moll., p. 7.

  • 1915. Vexillum apicale (Hutton): Suter, N.Z. Geol. Surv. Pai. Bull, No. 3, p. 20; Pl. 1, F. 5.

  • 1926. Proximitra apicalis (Hutton): Finlay, Trans. N.Z. Inst., vol. 57, p. 410.

Dr. Marwick informs me (in litt.) that “Buchanan's drawing, published by Suter, gives a very good idea of the appearance of this shell. The latter's statement that there are 25 nodules on the shoulder angle was based on two specimens from Awamoa mentioned as plesiotypes. They, however, differ much in shape from Hutton's holotype

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(which has now been found), and represent an undescribed species.” (Described later as Parvimitra pukeuriensis).

The type was from Awamoa, and my collection contains one topotype, one doubtful specimen from Rifle Butts, and eight shells from Pukeuri. The species is specially characterised by its high spire. There are 14-15 nodules per whorl, the body whorl rather small and slender, the spire angle about 35 degrees, the spirals with linear interstices, one or two stronger on periphery, and the keel median. Figures are here presented of an Awamoan topotype (Fig. 68), as a normal Pukeuri shell (Fig. 73—body whorl broken away), and a senile Pukeuri specimen (Fig. 72).

Dimensions of a normal Pukeuri shell, 7.8 × 4.5; of the senile figured shell, 15 × 5.3 mm.

Proximitra tumens n. sp. (Figs. 67, 69, 70, 71).

This occurs together with apicale, and may possibly be an extreme form of it, but the specimens are easily separated; tumens is the more common. It differs in its inflated shell and shorter spire (lower than aperture instead of subequal or higher), the angle of which is notably wider, about 45 degrees. The spirals seem exactly the same, but the shoulder nodules are more numerous, 17-21 per whorl, rather smaller and weaker than in apicalis.

Height, 17 mm.; width, 6.5 mm.

Locality—Pukeuri, sandy beds in the Road Cutting (Awamoan), type and 10 others; also Rifle Butts, Awamoa, All Day Bay blue clays, and Pareora shelly limestone (all Awamoan horizons).

Type in Finlay collection.

The Awamoa specimen here figured (Fig. 71; broken anteriorly) shows well the differences from the Awamoa apicalis.

Proximitra partinoda n. sp.

Has the same slender shape as apicalis, but spire shorter. Suture much more weakly margined. Shell smaller. Axial sculpture obsolete on body whorl, the nodules becoming very fine and close on penultimate and finally vanishing altogether, leaving last whorl smooth and rounded except for a faint trace of the peripheral carina. Spire whorls angled below middle.

Height, 10.2 mm.; width, 3.8 mm.

Locality—Blue Cliffs, Otaio River (Upper Ototaran?), type and two more shells; also Pareora River, blue clays (same horizon), two shells.

Type in Finlay collection.

Proximitra paucinoda n. sp.

Shell small, biconic. Embryo of two smooth whorls, as in tumens. Adult whorls four, rather flat, keeled almost at lower suture, body whorl sloping regularly from periphery to neck of canal, where it is slightly excavated. Axials about 11 per whorl, several times their width apart, very short, not reaching upper suture, and dying away just below periphery on body whorl; thin and sharp, but developed

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on periphery into strong nodules, swelling out on each side of the ribs leaving a sharp central ridge. Numerous spirals with sublinear interstices cover whole surface; four are considerably stronger on periphery and have deeper interstices; spirals above keel becoming weaker and thinner, leaving an almost smooth band below suture, which is not margined. Aperture as in tumens, but narrower, and sides more parallel.

Height, 11.5 mm.; width, 5.3 mm.

Locality—Blue Cliffs, Otaio River (Upper Ototaran?).

Type in Finlay collection.

Easily distinguished by its fewer and stouter nodules and low spire from the other species.

Parvimtra pukeuriensis n. gen. et sp. (Figs. 37-41).

Shell small, biconic, smoothish. Embryo of about two whorls, smooth, obscurely separated from adult whorls, initial coil very indistinct, closely wound. Subsequent whorls just over three, at first flat, later showing a keel a little above suture. Keel never very strong. Spire lower than aperture. 16-19 nodules per whorl on the keel, merely small tubercles, prolonged a small distance up and down to form short axials not reaching half way up shoulder, barely reaching lower suture. On body whorl axial ornament becomes practically obsolete, and there is usually only a smooth low keel. Spirals sub-obsolete, a few with linear interstices visible on base and on periphery. Aperture narrow, sides sub-parallel, angled above; beak short, un-notched. Pillar not excavated, with four sub-equal plaits, usually all oblique and sub-parallel, but occasionally the upper two more horizontal, the lower two sometimes a little weaker. Most specimens show persistent traces of irregular spiral anastomosing colour stripes.

Height, 7 mm.; width, 3.2 mm.

Locality—Pukeuri, sandy clays in road-cutting (Awamoan), type and numerous specimens. Also Awamoa (typical), Rifle Butts (five shells larger than Pukeuri specimens); and Target Gully (six shells; the common form from here is the next species).

Type in Finlay collection.

This is the species Suter used to identify as Vexillum linctum (Hutt.), which is a Pliocene Microvoluta.

This new genus is provided (with pukeuriensis as type) for a series of small species hitherto included in but disagreeing somewhat with Proximitra Finlay, 1926 (Trans. N.Z. Inst., vol. 57, p. 410). They are very much smaller than typical Proximitra, lack the rather long and twisted beak, usually show weaker sculpture, and have the pillar plaits somewhat differently developed. Proximitra has them set on a slightly excavated pillar, the upper three much stronger than the lowest (which is sometimes sub-obsolete), and widely separated, the length of the pillar below the plaits considerably greater than that above. Parvimitra has an unexcavated pillar, four sub-equal plaits or the lower two a little weaker, all plaits close together, the pillar space below less than that above or sub-equal to it. In Parvimitra may be included Austromitra plicifera Marwick, 1928 (Trans.

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N.Z. Inst., vol. 58, p. 485; F. 129) from Whenuataru Peninsula, Chatham Islands, Vexillum plicatellum Marshall and Murdoch, 1923 (idem., vol. 54, p. 123; Pl. 12, F. 3), from McCulloughs Bridge, and the new species described below.

On the other hand, Mitra (Cancilla) armorica Suter (N.Z.G.S. Pal. Bull. No. 5, p. 27; Pl. 12, Fig. 4), left by me under Mitra (Trans. N.Z. Inst., vol. 55, p. 468; Pl. 50, Fig. 4a, b), is undoubtedly a Proximitra, agreeing exactly with rutidolomum the genotype in apex, aperture, and general sculpture, but more elate, and with the whorls not bulging at the shoulder and regularly rounded instead of squarely truncate or even concave.

Parvimitra scopi n. sp.

Differs from pukeuriensis only in having stronger and fewer nodules (12-14 per whorl), tending to become wider apart on body whorl; the keel on body whorl is stronger, and the shoulder not so steep.

Same size as pukeuriensis.

Locality—Target Gully shell-bed (Awamoan), type and numerous specimens.

Type in Finlay collection.

This is the common Parvimitra here, and does not seem to occur elsewhere. Six shells from this locality could not be separated from pukeuriensis, the rest all agreed in their stronger and fewer nodules. Possibly scopi and ponsatanae (next species) are facies-forms of pukeuriensis, but as the Target Gully and Ardgowan horizon is probably a little lower than the typical Awamoan Pukeuri beds, and the specimens are separable at sight, it is best to give each a name.

Proximitra ponsatanae n. sp. (Fig. 29).

Another species closely related to pukeuriensis and scopi, but having numerous irregular axials instead of nodules. About 21 axials per whorl, very irregularly developed, interstices much narrower; they begin half way down shoulder and reach lower suture, on body whorl they become weaker below periphery but do not die away, and reach down to canal. They are only very feebly developed into nodules on periphery. No spiral sculpture. Four pillar plaits, the upmost and lowest rather weak, the second top one strongest.

Height, 7.3 mm.; width, 3.7 mm.

Locality—Ardgowan shell-pit (Awamoan).

Type in Finlay collection.

Recalls plicatellum (M. & M.) but that species has spiral sculpture, a margined suture, and more distant axials.

Parvimitra subplicatellum n. sp. (Figs. 43, 44, 45).

Shell very close to plicatellum (M. & M.), but more squat, and with stronger spiral sculpture. Spire whorls vertically compressed, the angle considerably greater than in plicatellum. About 21 axials per whorl, interstices twice their width or more, instead of fairly coarse ribs with sub-equal or narrower interstices. Strong spirals with linear interstices cover whole surface; the spirals in plicatellum

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Fig. 1.—Murersul scobina n. sp.: holotype × 23.
Fig. 2.—Murersul clifdencusis n. sp.: paratype. × 2.
Fig. 3.—Chicoreus (?) syngenes n. sp.: paratype. × 1.4
Fig. 4.—Chicoreus (?) syngenes n. sp.: holotype. × 1.4.
Fig. 5.—Poirieria primigena n. sp.: holotype. × 2.
Fig. 6.—Crosseola sultan n. sp.: holotype. × 3.
Fig. 7.—Chicoreus (?) komilicus (Sutei): holotype. × 11.
Fig. 8.—Murexsul clifdenensis n. sp.: holotype. × 2.
Fig. 9.—Pteronotus awamoanus n. sp.: holotype. × 5.
Fig. 10.—Dolicrossca awamoana n. sp.: holotype. × 4.
Fig. 11.—Crosseola proerrata n. sp.: holotype. × 12.5.
Fig. 12.—Crosseola proerrata n. sp.: paratype × 12.5.
Fig. 13.—Chicoreus (?) komiticus (Suter): topotype. × 2.3.
Fig. 14.—Murexsul (?) praegressus n. sp.: holotype. × 1.5.

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Fig. 15.—Verconella marwicki n. sp.: paratype × 0.9
Fig. 16.—Verconella marwicki n. sp.: holotype. × 0.7
Fig. 17.—Verconella parans n. sp.: holotype. × 2
Fig. 18.—Verconella affixa n. sp.: holotype. × 2.4
Fig. 19.—Verconella clifdenensis n. sp.: holotype. × 1.9
Figs. 20, 21.—Argalista proumbilicata n. sp.: holotype. × 9
Fig. 22.—Argalista proumbilicata n. sp.: paratype × 9
Fig. 23.—Scutus petrafixus n. sp.: holotype. × 0.7.

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Fig. 24.—Verconella sp.: Kapiti Island. × 1.3
Fig. 25.—Dolicrossea clifdenensis n. sp.: paratype. × 14
Fig. 26.—Dolicrossea clifdenensis n. sp.: holotype. × 14
Fig. 27.—Verconella parans (?) n. sp.: Pakaurangi Point × 23
Fig. 28.—Verconella allani n. sp.: holotype. × 0.6.
Fig. 29.—Parvimitra ponsatanae n. sp.: holotype. × 3.
Fig. 30.—Pleia otaioensis n gen. et sp.: holotype. × 2.1.
Fig. 31.—Cabestana debilior n. sp.: holotype. × 1
Fig. 32.—Verconella mandarina (Duclos): Kapiti Island juvenile × 1.3
Fig. 33.—Merica pukeuriensis n. sp.: holotype. × 5.
Fig. 34-36,—Parvimitra plicatellum (M. & S.): topotypes × 2.4
Figs. 37-40.—Parvimitra pukeuriensis n. sp.: paratypes. × 1.9
Fig. 41.—Parvimitra pukeuriensis n. sp.: holotype. × 1.9.
Fig. 42.—Parvimitra allani n. sp.: holotype. × 1.7.
Figs. 43, 44.—Parvimitra subplicatellum n. sp.: paratypes. × 1.8.
Fig. 45.—Parvimitra subplicatellum n. sp.: holotype. × 1.8.

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Fig. 46.—Notorola tainui n. sp.: holotype. × 0.7
Fig. 47.—Cordieria rudis (Hutton) electotype × 1.6
Figs. 48-50.—Cordieria rudis (Hutton): topotypes × 1.6 and 2.4
Fig. 51.—Magnatica fous n. sp.: holotype. × 2.8
Figs. 52, 53.—Cordieria huttoni n. sp.: holotype. × 2.4 and 1.6
Figs. 54, 55.—Cordieria huttoni n. sp.: paratype × 2.4 and 1.6
Fig. 56.—Notorola tainui n. sp.: paratype × 0.6.
Figs. 57, 58.—Cordieria haasti n. sp.: holotype. × 2.4 and 1.6
Fig. 59.—Cordieria haasti n. sp.: paratype × 1.6
Fig. 60, 61.—Cordieria verrucosa n. sp.: holotype × 24 and 1.6.
(Fig. No 62 is accidentally omitted.)

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Fig. 63.—Barbatia awamoana n. sp.: holotype. × 1.5
Fig. 64.—Barbatia awamoana n. sp.: paratype × 1.5
Fig. 65.—Barbatia awamoana n. sp.: paratype. × 2.6
Fig. 66.—Waimatea inconspicua (Hutton), var: McCulloughs Bridge. × 2.2
Figs. 67, 70.—Proximitra tumens n. sp.: paratype × 3.6
Fig. 68.—Proximitra apicalc (Hutton): topotype × 3.6.
Fig. 69.—Proximitra tumens n. sp.: holotype. × 3.6
Fig. 71.—Proximitra tumens n. sp.: Awamoa. × 3.4
Fig. 72.—Proximitra apicale (Hutton): Pukeuri, senile × 3.7.
Fig. 73.—Proximitra apicale (Hutton): Pukeuri, normal. × 3.6
Fig. 74.—Waimatea apicicostata (Sutei): McCulloughs Bridge. × 2.2.
Fig. 75.—Cosa wanganuica n. sp.: holotype. × 5.5.
Figs. 76, 77.—Cosa wanganuica n. sp.: paratypes × 5.5
Figs. 78-80.—Cosa filholi (Bernard) 60 fathoms, off Otago Heads × 5.5.

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Fig. 81.—Notovola lainui n. sp.: holotype. × 1.2
Fig. 82.—Notovola novaezelandiae (Reeve) 20-30 fathoms, off Otago Heads × 1

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are similar, but very weakly indicated, often obsolete. Aperture and pillar similar but shorter.

Height, 5.7 mm.; width, 32 mm. (corresponding measurements for the smallest of the three topotypes of plicatellum here figured, 7 × 3.5).

Locality—McCulloughs Bridge greensand below limestone (Tahuian), type and several other specimens.

Type in Finlay collection.

There seems to be no intergrading between these two species; the squat spirally sculptured shells are easily separated from the taller and smoother ones. For comparison, topotypes of plicatellum are here figured (Figs. 34, 35, 36).

Parvimitra clifdenensis n. sp.

Rather similar to plicatellum and subplicatellum, but smaller, with different axials and whorl shape. The whorls are regularly almost flatly convex, no median shoulder swelling as in those two species, merely a very faint indication of a shoulder angle. Sutures sub-canaliculate, but hardly interrupting the straight spire outlines. In general proportions similar to plicatellum, not subplicatellum. Differs from both these in absence of spirals. About 23 axials per whorl, sub-linear ridges, four or more times their width apart, prominent from suture to suture on spire whorls, completely vanishing half way down body whorl. Aperture and plaits as in pukeuriensis.

Height, 4.9 mm.; width, 2.4 mm.

Locality—Clifden, band 7A (Hutchinsonian).

Type in Finlay collection.

The absence of spirals and the numerous un-noduled axials recall ponsatanae (which possibly developed through this species from plicatellum); the Ardgowan species, however, is larger, has a well-developed shoulder, and much thicker axials, which do not reach upper suture.

Parvimitra allani n. sp. (Fig. 42).

Shell more slender than the other species of this group. Embryo of nearly two smooth whorls, the initial turn rather depressed. Adult whorls just over four, convex with a median bulge, hardly shouldered. Axials about 17 per whorl, rather low and blunt, interstices narrower, restricted to first two whorls which they cross from suture to suture, strongest medially; last two whorls smooth except for growth lines and obscure spirals; these are faintly developed over whole surface, with linear interstices, much as in plicatellum. Suture margined by a low but distinct band. Body whorl and spire long for the genus; four regular oblique equidistant pillar plaits, the lowest somewhat weaker.

Height, 8.2 mm.; width, 3 mm.

Locality—McCulloughs Bridge greensands, below limestone (Tahuian).

Type in Finlay collection.

This considerably resembles a young Waimatea, and differs from all the other Parvimitras in its slenderness. Nevertheless, the charac-

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ters of the apex, sculpture, suture, and canal seem to show closer alliance with plicatellum than with inconspicua and its relatives.

Waimatea amplexa n. sp.

Ancestral and very close to W. inconspicua (Hutton), from McCulloughs Bridge. Constantly more elongate and slender, and all examples seen are much smaller. The vestigial axials on the first adult whorl tend to be stronger and wider apart. The most marked difference is seen in the outline of the whorls at the sutures; in inconspicua there is a decided horizontal inturning just at suture so that the whorls appear somewhat staged, with a minute sutural platform, followed by a considerable convexity; in amplexa the whorls are tightly clasping, meeting in a steep angle, not staged, without a platform, and merely gently convex.

Height, 10.5 mm.; width, 3.7 mm.

Locality—Waihao Downs greensands, on the bank of the Waihao River (Bortonian), type and 5 more; also at the Abandoned Railway cutting (same horizon), one shell.

Type in Finlay collection.

This species is restricted to the Bortonian, whereas inconspicua is characteristic of the Tahuian. The latter species was recorded by Dr. Allan from Waihao Downs, but the present form was mistaken for it.

Waimatea apicicostata (Suter). (Fig. 74).

  • 1917. Vexillum apicicostatum Suter, N.Z. Geol. Surv. Pal. Bull. No. 5, p. 27; Pl. 12, F. 5.

  • 1926. Conomitra apicicostata (Suter): Allan, Trans. N.Z. Inst., vol. 56, p. 341.

  • 1926. Waimatea apicicostata (Suter): Finlay, idem., vol. 57, p. 408.

The position of this species is unsatisfactory. It was described from Geol. Surv. Locality No. 479—Marly greensands, Waihao River: McKay. It is somewhat uncertain whether this collection is from the upper or lower Waihao greensands; McKay records a separate locality as No. 642, Waihao River Bridge, which is presumably McCulloughs Bridge, so that the inference is that 479 is the Waihao Downs greensand. McKay's remarks in the Rep. Geol. Surv. Explor. for 1881, p. 72, strengthen this supposition, and the types of two species described from here, Hemifusus goniodes Suter and Clavatula mackayi Suter seems to be from the Downs greensand rather than McCulloughs Bridge. On the other hand, Surcula mordax Suter, Turris duplex Suter, and a paratype of Turris uttleyi Suter all agree better with McCulloughs Bridge shells than with Downs specimens. If Vexillum apicicostatum is from the Downs, it apparently must be the same as my W. amplexa, just described, as this is the only Waimatea found here. But the figure does not look like amplexa, having the short spire and convex body whorl of inconspicua. Exactly similar varieties of inconspicua occasionally turn up at McCulloughs Bridge, and one of them is here figured for comparison (Fig. 66). If this is Suter's shell, then it can hardly be maintained as distinct from incon-

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spicua. But his account of the sculpture seems to indicate a more strongly ornamented shell than inconspicua, which has only occasionally a few post-nuclear axials, and sometimes a few spirals on neck of canal, and 1-2 below suture. One specimen of a Waimatea, however, was collected at McCulloughs Bridge by Dr. Allan (Fig. 74), and this has, besides a more squat spire and inflated body whorl than any of the other forms, distinct spirals over the whole surface and well marked axials on all but last whorl. It seems preferable at present to identify this as apicicostata, and regard locality 479 as probably including two horizons, most of the species being Bortonian, but a few coming from a Tahuian band or locality. The matter, however, can only be cleared up by the Geological Survey.

Waimatea transilis n. sp.

Closely related to the Awamoan othoniana (Finlay), and ancestral to it. Spire lower, and body whorl relatively much larger and more inflated; whorls strongly instead of flatly convex. Ornament much weaker, shell almost smooth. The strong, close, reticulating axials on the early whorls of othoniana are absent, the merest trace of axial ribbing visible on only one specimen. Spiral sculpture much weaker, on spire whorls it is better developed on upper half instead of regular as in othoniana, practically absent on periphery; spirals on base numerous, low and rather broad, with linear interstices, instead of raised and rather distant ridges. Aperture somewhat wider, beak more quickly contracted. Other details same in both species.

Height, 10.8 mm.; width, 5 mm.

Locality—Otiake, sandy beds above limestone (Upper Ototaran), type and six others.

Type in Finlay collection.

This provides a bridge between othoniana and apicicostata; from the latter it differs in its weaker axials and stronger spirals and less sunken suture.

Verconella marwicki n. sp. (Figs. 15, 16).

Shell close to and probably ancestral to the Recent adusta (Phil.), but reaching a larger size, and more nodulous. On early whorls of adusta the axials are much more numerous and closer together, less than own width apart; in marwicki this is so for only the first post-embryonic whorl, the ribs rapidly becoming strong and distant, about twice their width apart; the closely costate appearance of adusta quite absent. The tubercles into which these ribs are raised are higher and much more regularly bluntly conical, not horizontally keeled by a peripheral rib; they are prolonged downwards on body whorl into rather narrowly raised ridges quite different from the wide undulations of adusta. Periphery lower down, on lower third of whorls instead of median. Spirals much lower and wider, separated by almost linear grooves, a broad and narrow one alternating, no strong raised ridges as in adusta. Shoulder clasping further up on previous whorl. Aperture perhaps a little longer. Other details as in adusta. Colour bands, as shown in a few specimens, paired, relatively much wider and less numerous than in adusta.

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Height, 129 mm.; of spire, 45 mm.; diameter, 63 mm.

Locality—Mt. Harris (Awamoan), type; not uncommon, better specimens than elsewhere. Also Target Gully, Ardgowan, White Rock River, Awamoa, etc. This is the common Awamoan Verconella.

Type in Finlay collection.

This species has been known for some time under a certain MS. name. As that has already been used for a species closely allied to and possibly really a Verconella, I name it as above. I have been awaiting the opportunity of associating Dr. Marwick's name with some specially fine shell, as a mark of admiration for his work on our Tertiary mollusca, especially his monographic studies of certain groups.

Fusus crawfordi Hutton, 1873 (Cat. Tert. Moll., p. 3), from East Coast, Wellington, is a much wider and stumpier shell, with the two angulations on the body whorl closer together.

Verconella koruahinensis Bart. and Powell, 1928 (Trans. N.Z. Inst., vol. 59, p. 146; Figs. 59, 60), from Kaawa Creek, has sharper nodules and periphery, and is considerably smaller.

Verconella accipitris n. sp.

Another species close to adusta, but somewhat smaller and more slender. Nodules rather low, much less prominent than in adusta (but becoming stronger on body whorl), and sooner fading away below periphery, sub-keeled by a peripheral cord; further apart on upper whorls, but not as much so as in marwicki. Spirals somewhat intermediate in character between those of adusta and marwicki, not so few and broad as in the latter, closer and lower than in the former, interstices not linear but narrower than ribs. Keel a little below middle. Whorls no more clasping than adusta but shoulder steeper and less concave, almost straight.

Height, 100 mm.; width, 50 mm. (type).

Height, 70 mm.; width, 35 mm. (paratype).

Locality—Hawke's Bay, several Nukumaruan localities; Okauawa Stream (type), Maraekakaho-Kereru Road (paratypes). Collected by Dr. R. S. Allan and C. R. Laws.

Type in Finlay collection.

Verconella interjuncta n. sp.

Shell intermediate between marwicki and asper Marwick, 1928 (Trans. N.Z. Inst., vol. 60, p. 485; F. 131). It has the strong regular spirals of asper, though apparently more of them. The shoulder is above the middle, though not quite as high as in asper (at lower third in marwicki). Consequently the axial ribs are much longer and more prominent on spire whorls than in marwicki, and much less tubercular, being hardly more raised on periphery; they are closer together than in marwicki (about 1½ times their width apart), but not so close as in asper (where they are less than own width apart). In other details like marwicki.

Height, 55 mm. (body whorl only); width, 35 mm.

Locality—Clifden, band 8A (Awamoan?), type; also some broken shells from band 7C (Hutchinsonian).

Type in Finlay collection.

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Verconella affixa n. sp. (Fig. 18).

Another species of the marwicki-adusta line, characterised by almost straight whorls and strong coarse spirals. Keel lower down than in any other species, practically at suture so that tubercles are just visible on spire whorls, which are almost straight, the spire itself having a faintly concave outline. Spirals strong and very irregular, like those of adusta in being narrow and raised, but not quite so strong, and still more irregular in disposition; not like the flat cords of marwicki, the difference being especially noticeable on periphery. Axials like those of marwicki but straight, not convex. Numerous lirae well within aperture. Periphery more carinate and canal shorter than in marwicki. Shell apparently small, but probably not full grown.

Height, 34 mm.; width, 19 mm.

Locality—Clifden, band 6C (Hutchinsonian), 1 shell.

Type in Finlay collection.

Although this species has a still lower placed keel than the Awamoan marwicki, interjuncta from the next set of beds has the high keel of asper; either more than one line is represented, or these are depth differences similar to those observed in Recent shells; bands 7 and 8 were evidently deposited in shallower water than band 6.

Verconella clifdenensis n. sp. (Fig. 19).

Shell rather small, very spiny, extremely like Fusinus kaiparaensis Suter in general aspect, but with a Verconellid canal and apex. The latter is of 3-3½ smooth convex whorls, cylindroconic, first whorl very rapidly increasing from the minute adpressed tip, equal in diameter to next whorl and somewhat overhanging it on one side; there is a slight but distinct subangulation low down on its whorls, and it ends in a small varix. This is as described by me for Verconella as distinct from Austrosipho Cossmann (Trans. N.Z. Inst., vol. 57, p. 504; 1927), and as figured by Powell for the Recent dilatata Q. & G. (idem., p. 550; F. 8 in text). First adult whorl with 7 axials, these increase to 8 or 9 on central whorls, but may return to 7 again on later ones; thick and stout, at first extending from suture to suture, though narrower on shoulder, later becoming subobsolete on shoulder, but much heavier and stronger from periphery to lower suture, projecting on periphery as long sharp and strong spines, vertically compressed, and keeled by a spiral cord on periphery; directed out and at first slightly up, but when senile tending to point down; axials rapidly diminish below periphery and cease at a basal angulation marked by a strong cord, which is also rendered tubercular (the tubercles here being very narrow and elongated). Spirals even and fine on shoulder (interstices about twice their width, with an interstitial hair-thread); irregular on base, two equidistant stronger ones between periphery and lower angulation, with weaker ones between, and still weaker ones between these; a similar arrangement down on to neck of canal except that main spirals get closer. Aperture and canal typical, as in adusta and dilatata, etc., but when senile the fasciole is enormously developed, and circles outwards in a strong sharp carina enclosing a small umbilical chink. Adult whorls 6-7, strongly carinate at lower third or fourth.

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Height, 41 mm.; of spire, 16 mm.; width, 26 mm. (type). The species reaches at least 65 mm. height as shown by imperfect paratypes.

Locality—Clifden, band 6C (Hutchinsonian), type and several others; and band 7A (Hutchinsonian), two shells. Also two broken shells apparently of this species from the lower shell-bed, upmost Mt. Brown beds, Weka Pass.

Type in Finlay collection.

This seems to be on a different line from marwicki and adusta, and probably represents Powell's “Group A” which contains true dilatata Q. & G., and is “confined to deep water” with a “comparatively thin shell.” In shape it considerably resembles V. koruahinensis Bart. & Powell, from Kaawa Creek, but has stronger, sharper and more compressed tubercles, and a much more prominent basal angulation.

From a horizon in the third bay at Clifden, somewhere between 6C and 7A, Dr. Thomson collected two fine specimens (in Dominion Museum collection) which show the senile characters well; the strongly keeled fasciole gives them a superficial resemblance to Austrofusus magnificus Finlay, from the same beds.

This is the “undescribed” species which Powell and Bartrum (Trans. N.Z. Inst., vol. 60, p. 431) have stated to be the nearest relative to their V. exoptata from Waiheke Is.

Verconella parans n. sp. (Figs. 17, 27).

Directly ancestral to clifdenensis. Shell more slender, spire angle considerably smaller, body whorl not nearly so wide. Spines much smaller and less developed, mostly as blunt tubercles on axials, hardly at all vertically compressed, periphery generally with 2-3 strong spirals instead of one. Periphery submedian instead of near lower suture. Canal less bent to left, and fasciole weaker.

Height, 40 mm.; of spire, 19 mm.; width, 19.5 mm. (type). Largest specimen reaches 53 mm. in height.

Locality—Clifden, band 6B (Hutchinsonian), type and several others; also bands 6A and 4B (Hutchinsonian).

Type in Finlay collection.

In my collection is a shell from Pakaurangi Point (Fig. 27) which I tentatively identify as this species. I can find no separative characters except the protoconch, which is of only two whorls and smaller than that of parans. But the apex of parans is not constant in size; though always of the same general type, some specimens may have it up to twice as large as others. This is exactly what Powell has noticed (Trans. N.Z. Inst., vol. 60, p. 61; Figs. 118-121; 1929) in the Recent adusta, and is a common feature in genera which produce several larvae in each ovicapsule. So, although the Pakaurangi shell has a smaller embryo, of fewer turns, than any Clifden specimen of parans, I prefer to leave it there till more than one specimen shows its constancy or otherwise.

The small size of the apex in this Pakaurangi shell and in Siphonalia excelsa Suter induced me to refer them to Austrosipho (Trans. N.Z. Inst., vol. 57, p. 504; 1927) but now I very much doubt this.

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Austrosipho has the same protoconch as true Colus (described by Grabau, whose account is quoted by me elsewhere in this volume), and there are rather characteristic differences in the ornamentation from Verconella. I cannot satisfactorily place excelsa; it seems not unrelated to such Balcombian species as asperulus and styliformis Tate, but these are not typical Austrosipho. The lineages in this group are most complex. If genera are to express lineages, I do not see how Largisipho Iredale (Rec. Austr. Mus., vol. 17, No. 4, p. 182) can be maintained as distinct from Austrosipho; L. spectanda, the genotype is evidently a terminal Recent member of the Tertiary roblini line.

Verconella mandarina (Duclos). (Fig. 32).

This species occurs at Castlecliff, but I have not seen it from a lower horizon. Juveniles are common there and agree well with Recent juvenile shells, one of which (from Kapiti Island) is here figured. Powell (Trans. N.Z. Inst., vol. 57, p. 556; 1927) gives Wanganui as the most northerly locality for this species known to him, but I have several typical shells from Kapiti Island.

Verconella falsa n. sp.

1926. Verconella dilatata (Q. & G.): Finlay, Trans. N.Z. Inst., vol. 57, p. 412; Pl. 20, F. 70; not of Q. & G.

Powell's work on the Recent Verconellas from the littoral down to 105 fathoms shows that I misidentified Quoy and Gaimard's species. I stated at the time that the identity of this species could not be settled till exact topotypes were dredged. Powell has now figured a 25 fathom shell (Trans. N.Z. Inst., vol. 57; Pl. 30, F. 18; 1927) which may be taken as typical, and this does not agree with my Castlecliff shell. This has very fine spiral sculpture in comparison with adusta or mandarinoides, a very short canal, and incipient tuberculation on last three whorls. The tubercles are never much developed, and have not the characteristic double spiral ridge of the dilatata series; the whorls are very convex, with a blunt sub-angle above the middle.

Height, 117 mm.; of spire, 53 mm.; width, 60 mm.

Locality—Castlecliff “papa” (Castlecliffian).

Type in Finlay collection.

Verconella allani n. sp. (Fig. 28).

This is an interesting form ancestral to falsa. It has the same fine spiral sculpture and regular close axials (as in mandarina) on early whorls, but the subsequent axial sculpture is quite different, and at present unique in the genus. After the first 3-4 whorls, the close axials die away altogether, and the next two whorls are devoid of axial sculpture, regularly rounded, the even spiral sculpture interrupted only by growth lines. On the body whorl or just before it axial sculpture reappears again and remains up to aperture, but now there are no ribs but prominent tubercles (on the paratype they are much higher and stronger than on the figured type), much like those of adusta, 10-11 per whorl. Aperture as in mandarinoides, etc.

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Height, 129 mm.; of spire, 56 mm.; width, 61 mm.

Locality—Nukumaru, “papa” band (Nukumaruan), type and one paratype, collected by Dr. R. S. Allan.

Type in Finlay collection.

The loss of axial sculpture on the median whorls is the most characteristic feature of this species, but it is also more slender than falsa, the whorls are more tightly clasping at the sutures, and the canal is longer. Apart from these differences, falsa might be regarded as an allani in which the change from simple axials to nodules took place without the intervention of a smooth space; i.e., the stages of growth are telescoped. This is what one might expect in a descendant.

Verconella sp. (Fig. 24).

At Castlecliff, juveniles of two different species are common. One has very coarse spiral ridges and numerous close axial ribs; this I identify with mandarina. The other has much finer spirals and rather distant axial ribs (1½–2 times their width apart) on first 3¾ whorls, last whorl and a quarter without axials; the axials become slightly nodular on periphery of second whorl, and remain so till penultimate whorl, where the ribs tend to disappear, leaving only nodules, then these too disappear. The apex is large, of about four swollen whorls, the first somewhat planorbid but exsert, the tip minute, the others very globose and overhanging the normal conch. A single Recent shell (the one figured) from Kapiti Island shows exactly the same features, and almost certainly represents the same species. What that is I am not sure. The distant axials and other apical features indicate alliance with V. rex Finlay, but this species and the other benthal relatives of dilatata are always strongly keeled and have very prominent triangular vertically compressed nodules. Perhaps it is the young of falsa, but it seems too slender. It might equally well be a juvenile of ormesi Powell, which is the only species of this group in which axials soon become obsolete. Until they can be traced up to the adult, and the body whorl sculpture and proportions determined, it seems useless to attempt identification. Ormesi is much more slender than falsa, but very likely descended through it from allani.

Dimensions of figured specimen (in Finlay collection): Height, 55 mm.; of spire, 24.5 mm.; width, 23 mm.

Murexsul (?) clifdenensis n. sp. (Fig. 2, 8).

Protoconch polygyrate, of at least three smooth conical whorls, the tip minute (but worn), apparently ending in a faint sinusigeral varix; not like the apex I described for octogonus (Trans. N.Z. Inst., vol. 57, p. 487; 1927). Adult sculpture follows immediately; 7 axials per whorl, stouter and more raised than in octogonus (which has 9 per whorl), and the hollows between deeper, so that the spirals are much more undulated than in octogonus. Spirals very dense and fine on shoulder, spreading out fan-wise at the varices, a few central ones stronger and further apart; 3 main spirals on body whorl, 1 on keel,

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1 emerging from suture, and 1 a little below this, then a wide excavated space with only fine spirals, then one very strong oblique rib on neck of canal (occasionally with a much weaker one close to it just below), then fine spirals to fasciole which is but slightly stronger than the neck cord; between peripheral and lower sutural spirals there are 2 (closer to suture) stronger than the other interstitials, these appear just above suture on spire whorls. Covering whole surface between main spirals are fine raised threads of irregular width and development, but a space above and below peripheral keel is always free of all but the finest threads. Axials raised into sharp hollow spines on periphery and on neck cord, and to a less extent on other main spirals and fasciole; fine and numerous hollow curved lamellae on growth lines render all spirals rasp-like. Whorls (excluding apex) about 7, with a median keel, the shoulder sloping at about 30 degrees, straight below. A slight swelling margining suture below. Aperture not fully formed in any specimen, but probably like that of next species described. Pillar with a very strong twist and strong subangulation at inception of canal, which is short, only about half that of octogonus.

Height, 23 mm.; of spire, 9 mm.; width, 14 mm.

Locality—Clifden, band 6C (Hutchinsonian), type and 4 paratypes.

Type in Finlay collection.

This represents a different line from octogonus, but may be left under Murexsul till the group is revised.

Murexsul (?) praegressus n. sp. (Fig. 14).

Protoconch missing, but shell almost certainly of same group as and ancestral to clifdenensis. Apparently larger and with more even spiral sculpture. Axials and spines same in number and arrangement, except that spirals below periphery carry stronger spines. The same smoothish space above and below periphery, but elsewhere spirals are much more regularly arranged than in clifdenensis; 4 strong cords with narrower interstices below this space on penultimate whorl; 6-7 main spirals on body whorl with a weaker interstitial riblet between each pair; 2 spiny raised cords on neck of canal, close together, the lower stronger, less oblique than in clifdenensis. Aperture rather narrowly oval, with thick walls, everywhere projecting, strongly separated from body and parietal walls, channelled at periphery and at suture, with 7 internal denticles; pillar with same strong twist and angulation as clifdenensis, with a prominent tubercle on inner lip at end of twist and a fainter one above. Canal as in clifdenensis, but fasciole more curved and spreading, enclosing a deep umbilical perforation.

Height, 33 mm.; of spire, 14 mm.; width, 22 mm.

Locality—Clifden, band 3 (Hutchinsonian).

Type in Finlay collection.

The two denticles on the columella are highly abnormal in the genus; they are not seen on any specimens of clifdenensis, but probably none of these are fully adult.

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Murexsul scobina n. sp. (Fig. 1).

Very like praegressus, but smaller, more slender, with 8 axials per whorl. At first sight the specimens seem to be juveniles of praegressus, but the number of axials is constant in all specimens seen, the canal is longer, the umbilical chink practically absent, and the spines on all but the peripheral rib are less prominent. The spiral sculpture is different, every fourth rib being stronger, and all the spirals are minutely and densely covered with tiny hollow foliations, giving a very file-like surface to the shell; 3 central spirals on shoulder are rather stronger. Two spiral cords on the whorls (on keel and near lower suture) are generally much stronger than the others. Three stronger oblique raised cords on neck of canal, the two top ones distant and always the most prominent, the lowest close to the median one, and sometimes inconspicuous.

Height, 18 mm.; of spire, 7.5 mm.; width, 10 mm.

Locality—Clifden, bands 4B (3 shells), 6A (type and 2 others), and 6B (1 shell). Also one shell from Target Gully.

Type in Finlay collection.

Two of the specimens from 4B (width about 28 mm.) indicate that this species reaches a much larger size—comparable with octogonus, of which this is probably an early ancestor. Unfortunately the protoconch is absent in all specimens, but I think it would prove to be paucispiral and quite different from clifdenensis and praegressus. The arrangement of spiral sculpture, especially the canal cords and the two prominent spirals on upper whorls is so like octogonus that I have little hesitation in referring it to this line.

This type is not unrelated to such Australian Tertiary forms as Murex eyrei Ten.-Woods (Table Cape) and Rapana aculeata Tate (Muddy Creek), but these species have different whorl proportions, a relatively higher and wider spire, different spines, and probably a larger embryo.

Chicoreus (?) komiticus (Suter). (Figs. 7, 13).

  • 1917. Murex zelandicus var. komiticus Suter, N.Z. Geol. Surv. Pal. Bull. No. 5, p. 37; Pl. 4, F. 21.

When Suter described this Pakaurangi Point shell, it was mostly embedded in matrix, as shown by his figure, and no attempt was made to remove this. Suter was apparently quite satisfied that the fractured section exposed indicated alliance with the Recent zelandicus, but the details of the sculpture should have made him suspicious. When examining the holotype in the Otago Museum, I took the opportunity of removing the soft matrix and exposing the back of the shell. The figure of this now presented (Fig. 7) will sufficiently indicate how far from the mark was Suter's guess. The species is generically distinct from Poirieria zelandica (Q. & G.), and represents a type of Murex not hitherto found in New Zealand. The misleading comparison makes Suter's description worthless, and the species may be redescribed as follows:

Protoconch polygyrate (mostly missing in all specimens seen), conical, of several smooth almost flat whorls, with a curious lamellar keel exactly at the suture, jutting over the following whorl, termina-

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tion obscure, but apparently sinusigerid. 5½ adult whorls, at first convex, then subangled, then bluntly keeled below middle, body whorl with a strong but not sharp keel. Axials 12 on first whorl (no varices), extending evenly across whorl, interstices about same width; varices develop on next whorl (3 per whorl), and become gradually stronger and stronger till on body whorl they are prominent and thick, rising suddenly and concave behind, sloping gradually but ending in a sharp edge in front; 2 axials between varices, at first equidistant and little different from the varices in size and shape, but they gradually shift forward (toward the anterior varix), the front axial diminishes, and the hinder one increases in size, till on the penultimate and especially body whorl there is apparently only one large central nodule between varices, with remnants of an axial prolongation above and below it, the front axial being now represented only by a thin ridge close to the anterior varix. Varices markedly prolonged on to base and jutting out as former ends of canals. Spirals at first 4 per whorl, equidistant, but the topmost one (on shoulder) weaker, gradually more and more spirals are intercalated till whole surface is covered with dense spiral sculpture, 2 more prominent on periphery and about 6 below, and 3-4 on shoulder; between these is a finer interstitial riblet, and between these again 1-3 very fine threads, the interstices irregular but mostly wider; the whole finely netted by hair-like axial threads. On the varices the main spirals are much stronger and raised into sharp narrow spines (mostly broken off), triangular and hollow in front; the peripheral spine is especially long and strong, on their backs they bear radiating distant narrow ridges. Three stronger cords with stronger spines on neck of canal, the upper two more distant. Aperture as described for praegressus, but more circular, lips not so thick and projecting (the inner one hardly separated from body whorl), the same two denticles on inner lip, but weaker. A distinct but small umbilical chink, fasciole strong, broken up by prolongation of varices.

Two other specimens from Pakaurangi Point are in my collection, one of these is here figured (Fig. 13) to show the normal appearance of the species. Its dimensions are: Height, 31 mm.; of spire, 13 mm.; of aperture, 10.5 mm.; width. 22 mm. The type is somewhat abnormal in its deeper sutures and excessively spinose condition.

The generic placing of this and the following species is difficult. To an austral worker the Muricoid genera are in a very unsatisfactory state. Cossmann's treatment in the Ess. Pal. Comp., vol. 5, is obviously inadequate, Harris's locations of Australian Tertiary species need revision, Dall's works are concerned more with American species, and the only trustworthy general review commonly available is Iredale's sketch in Trans. N.Z. Inst., vol. 47, pp. 467-471; 1915. This does not pretend to be exhaustive, and merely mentions types of genera, so that I find it very difficult to locate species that do not belong to Murexsul or Poirieria. Komiticus and the next species are obviously related to such Tertiary Australian species as lophoessus Tate (Trans. Roy. Soc. S.A., vol. 10, p. 98; Pl. 2, F. 5; 1888) and two allied new species from the Abbatoirs Bore, Adelaide; such a Recent species as turbinatus Lamk. seems also connected. They are not Murex s. str., Hexaplex, or Pteronotus, so for the preesnt I leave

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them in Chicoreus, the fourth of the “outstanding genera” mentioned by Iredale (l. c., p. 469), though the resemblance to ramosus L., the genotype, is but faint.

Chicoreus (?) syngenes n. sp. (Figs. 3, 4).

This is so closely allied to komiticus that it can best be described by comparison—for that reason I have given a very full description of komiticus. Apex worn, but enough remains to show that it was of same style. Same shape and size, and same arrangement of sculpture. Peripheral spikes not so long and strong, not hollow (closed up by shell substance), with much weaker radiating ridges on their backs. Varices less conspicuous, especially on early whorls, less raised and not concave behind; the anterior of the two intermediate axials disappearing more completely, hardly a trace left on body whorl. Only one prominent oblique rib on neck of canal, but this is much thicker and stronger and more spinose than any of the three in komiticus, and has only fine spirals on each side of it.

Height, 32 mm.; of spire, 12 mm.; of aperture, 11 mm.; width, 20 mm.

Locality—Clifden, band 6C (Hutchinsonian), type and one other. Also one much rubbed shell from band 3.

Type in Finlay collection.

Poirieria primigena n. sp. (Fig. 5).

Directly ancestral to the Recent zelandicus Q. & G. Differs at sight in much lower position of keel, which is below middle of whorls instead of above. The whorls are consequently less tabulated and more pagodiform. These differences are constant, but otherwise the species are exactly the same. Evolution in the sculpture of this genus seems to have been at a standstill since our first knowledge of it in New Zealand.

Height, 38 mm.; of spire, 13 mm.; of aperture, about 12 mm.; width, 28 mm.

Locality—Otiake, sandy beds above limestone (Upper Ototaran), type and three fragments. More or less well preserved specimens also from Blue Cliffs and Pareora River (same horizon), Target Gully, Ardgowan, and Pukeuri (Awamoan).

Type in Finlay collection.

P. zelandica persists downwards at least as far as the Nukumaruan, a typical specimen being in my collection from Maraekakaho, Hawke's Bay. Where the break between the two species occurs I am not certain. Primigena is a very old species, Tahuian and Bortonian specimens (McCulloughs Bridge, and Abandoned Railway, Waihao Downs) being inseparable from the Otiake type; the apex appears to be smaller but is worn.

Pteronotus (s. str.) laetificus n. sp.

Shell large, only body whorl remaining. Three varices on this, thick and wedge-like, outline fairly regularly convex, apparently not spinose except at periphery, where there is a single strong broadly triangular projection, quite flat in front, with no trace of a groove, merely triangular growth lines; slightly angled behind. A single

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stout but low and blunt elongated tubercle midway between varices. Heavy, low, and not prominent spiral cords over whole surface, about 14 in number, weaker on shoulder. Aperture rather narrowly oval, outer lip more convex than inner one, channelled above, leading into a fairly long open (?—the sole specimen has the lips of the canal broken) canal. Outer lip adpressed to flange, its margin little but distinctly raised, then rapidly contracting anteriorly to a blunt angulation on which are 8 short stout distant tubercles.

Height (of body whorl), 48 mm.; width, 41 mm.

Locality—Clifden, band 7C, close to band 8 (Hutchinsonian).

Type in Finlay collection.

Nothing like this has previously been seen from New Zealand, though I have fragments of a second new species of this group from Target Gully. Laetificus does not belong to the group containing the Recent Tasmanian triformis, but rather to that of the Balcombian calvus Tate, which is perhaps allied to the Chinese pinnatus Wood, the genotype of Pteronotus. The New Zealand shell is much larger and wider than calvus.

Pteronotus (Pterochelus) awamoanus n. sp. (Fig. 9).

Shell extremely close to the Recent eos (Hutton), but much smaller, and more slender, the two main keels closer together. Perhaps the best separative feature is the outer lip of the aperture, which in eos stands out at right-angles to the frill and is merely crenulated; in awamoanus it is effuse and flexed over till it is almost parallel to frill, and carries 5 teeth inside, remarkably solid for so small a shell. That portion of the outer lip between spike and suture is also markedly more steeply descending in awamoanus. Protoconch paucispiral, almost the same as in Murexsul octogonus.

Height, 16.6 mm.; of spire, 7.5 mm.; width, 8 mm. (type).

Height, 10.5 mm.; of spire, 4.5 mm.; width, 5 mm.; (paratype).

Locality—Target Gully shell-bed (Awamoan), type and 14 more or less fragmentary specimens. Also Ardgowan.

Type in Finlay collection.

The Castlecliffian P. zelandica (Hutt.) (Typhis), which intervenes between this species and eos is more different from them both than they are from each other, but it seems probable that it belongs to a different line, and that an eos type also occurs at Castlecliff.—I have no specimens, but I think there is one in the Geological Survey collection.

Zeadmete pliocenica n. sp.

Shell very close to the Recent Z. trailli (Hutton), and evidently directly ancestral to it. The chief difference is the possession of a well-marked shoulder a little below the suture (much as in Oamaruia), so that the whorls are quadrate, with vertical sides and an almost horizontal platform above; trailli has no angle, the whorls regularly convex, the body whorl quite ovate. Sculpture stronger, the cords being alternately weaker and more prominent, while in the Recent species they are less conspicuous and more even. Aperture relatively narrower, and the pillar plaits weaker, especially the median one.

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Height, 9.3 mm.; width, 4.6 mm.

Locality—Castlecliff “papa” (Castlecliffian), type; also Petane (Nukumaruan).

Type in Finlay collection.

Zeadmete miocenica n. sp.

This merely carries to a further degree the differences from trailli shown by pliocenica. The shoulder is still sharper, and a little lower down. The peripheral cord and the one below it are more prominent and further separated than the others, giving a bicarinate appearance to the whorls, while in pliocenica the four main cords on the vertical part of the whorls are equal and practically equidistant. The pillar plaits are still weaker; the lowest (which is really merely a sharpedged twist of the pillar in pliocenica and trailli) is barely evident, and the two upper ones are feeble, almost horizontal and close together, much like the plaits in the Turrid genus Mitrithara. Apex as in the other two species, of about 1¼ whorls, smooth and polished, upright, loosely coiled, the tip prominent and globose; marked off (but not prominently) from adult whorls by a very faint varix.

Height, 5.6 mm. width, 3 mm. (probably not fully grown).

Locality—Pukeuri, sandy clays in the road-cutting (Awamoan), type and one other; also Rifle Butts (Awamoan), two shells.

Type in Finlay collection.

Oamaruia (?) nodus n. sp.

Shell ovate, regularly and closely fenestrate. Embryo smooth and polished, of about 2¼ whorls, well and somewhat flatly coiled, vertically compressed, the top flattened and somewhat planorbid, the tip adpressed but prominent. A few curved axial riblets intervene between the faint closing varix and the true adult sculpture. This consists of spiral cords and stronger axial ribs, both numerous. There are at first 4 spirals, 1 on shoulder, other 3 below; these increase and become alternately stronger and weaker and about their own width apart (about 11 altogether on penultimate whorl; about 27 and half-a-dozen finer canal threads on body whorl). Axials 22 on body whorl, sharp, twice their own width apart or more, slightly sigmoid, extending almost undiminished from suture to base of canal; the two top spirals are more crenulated than the others by the tops of the axials. Outer lip and base of pillar broken away. Pillar plaits three, the lowest being on the twist of the canal, the upper two strong, sharp, oblique, and rather distant; weak ridges and grooves are intercalated between the plaits towards their extremity. Apparently a decided beak present.

Height, 11 mm.; width, 5.5 mm.

Locality—Otiake, sandy beds above limestone (Upper Ototaran).

Type in Finlay collection.

This is an anomalous form. It does not match with any New Zealand or Australian species that I know, and is temporarily referred to Oamaruia on account of the strong pillar plaits, but the shape and sculpture are more like Zeadmete; the embryo is not in accord with either of these groups.

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Merica pukeuriensis n. sp. (Fig. 33).

Shell ovate, rather rotund, much the shape of a Bonellitia, but with a straight unexcavated pillar and different apex. Protoconch polygyrate, of 3½ smooth convex and shining whorls, well coiled, with rather deep sutures, the tip small, flattened, almost planorbid, the last ¼ volution with three keels, the upmost on the shoulder and very weak, the median one at the peripheral angle and strong and sharp, the lowest midway between this and suture, not so strong. With the inception of axial sculpture these keels become the three main (and on first whorl only) spirals in the adult sculpture; on the second whorl a slightly weaker spiral is intercalated between each, while on the third and last shell whorl the spirals become subequal, about 15 in all, narrow and raised, 2-4 times their own width apart. The topmost spiral on all whorls marks a sharp raised ridge between which and suture there is a deep sunken channel crossed only by lamellar axial ridges. Axials 16 per whorl, extending across the sutural ditch as irregular low lamellae, thence passing strongly from the bordering keel to the base, weakening slightly near end of canal; they are slightly oblique backwards, strong but narrow, about three times their width apart, undulating the four top spirals (especially the close topmost two), but not much affecting the others, hardly tubercular at intersections. Aperture trigonal (outer lip incomplete), horizontal at the suture, thence broadly and regularly curved to meet pillar in a point, canal almost absent, vertical and open. Three pillar plaits, progressively stronger posteriorly, subequidistant and very oblique. Basal fasciole marked by a very slight swelling.

Height, 13 mm.; width, 9 mm.

Locality—Pukeuri, sandy clays in road-cutting (Awamoan).

Type in Finlay collection.

This seems not distantly related to the common Australian Kalimnan Cancellaria wannonensis Tate (Trans. Roy. Soc. S.A., vol. 11, p. 156; Pl. 8, F. 11; 1889), which in turn is obviously ancestral to the Recent undulata Sow., common in New South Wales and Tasmania. At first sight the excavated sutures are more reminiscent of spirata Lamk. and lactea Desh. (=laevigata Sow.), but the protoconchs of these two Australian species are large and paucispiral, like Maorivetia Finlay. Wannonensis and undulata have a flat platform instead of an excavation at the suture, but otherwise the type of ornament is identical, and their apices are the same as in pukeuriensis, except in being more exsert and lacking the closing keels—these are not vital differences. They are longer shells, with a better developed anterior beak, but the similarity is sufficiently close to associate the New Zealand species with them.

Judging from the figure and description, I should say that Admete maorium Marshall and Murdoch (Trans. N.Z. Inst., vol. 53, p. 82; Pl. 18, Figs. 7, 8; 1921), from Target Gully, is close to pukeuriensis and certainly congeneric with it. I have seen no specimens (the type is apparently unique), but the same kind of sculpture and sutural excavation are evident from the figure, though it was a more juvenile shell than pukeuriensis. It differs in its stronger spiral sculpture and fewer axials (12), forming rather deep square pits between them.

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These shells are widely removed from Voluta reticulata L., the genotype of Cancellaria. Following Cossmann in the meantime, I have placed them in Merica H. & A. Ad. (the type of which he gives as melanostoma Sow.), for which he used and figured wannonensis as a “plesiogenotype,” but they do not fit very well. In the absence of comparative Recent material, I am unable to suggest a better location.

Uxia naroniformis n. sp.

Shell much like Narona in form, with sub-spiny sculpture, and produced body whorl and beak. Embryo tiny, paucispiral, of 1¼ loosely coiled smooth and shining whorls, the tip bulbous, prominent, set askew and slightly inrolled; not well marked off from adult sculpture. Three main narrow and sharp spiral cords on spire whorls, the upper two twice as far apart as lower two; 5 more equally prominent cords on body whorl, all but the topmost one equidistant and 4-5 times their width apart; on the shoulder, in interstices, and on canal are a few distant linear spiral threadlets. About 12 axials per whorl, stout and blunt, hardly oblique, antecurrent on shoulder, and rapidly diminishing towards suture, continued over body whorl and base, vanishing only at extremity of canal, 2-3 times their width apart; intersections of spirals and axials marked by sharp prickles, especially on two top spirals. Adult whorls 5, strongly shouldered at upper three-quarters, platform gently sloping, sub-vertical below. Last whorl long, about three-fifths of entire shell. At irregular distances there are strong flattish varices, 3 on the actual specimen, 1 just before the unformed outer lip; they are the general shape of the axials, but stronger and wider and more prominently antecurrent on shoulder. Aperture elongated, beak rather long, canal open, bluntly pointed, not channelled. Parietal wall smooth; three strong equal and equidistant pillar plaits; a strong basal fasciole.

Height, 16 mm.; width, 7.5 mm.

Locality—Rifle Butts, sandy clays (Awamoan).

Type in Finlay collection.

Quite close in details to the Tahuian Uxia marshalli Allan, though at first sight superficially different in the unchannelled suture. The number and the arrangement of the spiral and axial ribs are the same, but marshalli has much thicker and more prominent interstitial spirals, a channelled suture so that tops of axials project as blunt points, a shorter body whorl and beak, weaker fasciole, and less oblique plaits on the columella.

Uxia marshalli Allan.

1926. Uxia (?) marshalli Allan, Trans. N.Z. Inst., vol. 56, p. 342; Pl. 77, Figs. 3a, b.

This is very close to the Australian Balcombian Cancellaria epidromiformis Tate and exaltata Tate (Trans. Roy. Soc. S.A., vol. 11, p. 154; Pl. 8, Figs. 9, 10; 1889), having the same channelled suture, and arrangement of spiral and axial ribs (the latter more numerous on the Australian species), but a considerably lower spire; the Balcombian species have the appearance of being drawn out and

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unwound, so that more spirals show on the spire whorls (5 instead of 3). They also have a much larger apex, though of exactly the same style. The parietal plait is irregularly developed but present in all these species; naroniformis does not show it, but is not quite adult.

In the absence of specimens of the genotype of Uxia Jousseaume, 1888 (Cancellaria costulata Lamk.; Eocene, Paris Basin) I am not certain that these austral species are correctly placed generically. Cossmann's figure (Ess. Pal. Comp., livr. 3; Pl. 1, Figs. 16, 17; 1899) of the genotype has a different look, with its apparently more symmetrical and larger apex, weaker spiral sculpture, and widely open, not pointed, distinctly shallowly notched anterior canal; but on the other hand, several of the species illustrated as Uxia by Cossmann in the Icon. Comp. Coq. foss. l'Eogene Env. Paris, Tome 2; Pl. 47 (e. g., Figs. 212-4, 7, and 12) are so like exaltata and marshalli that it seems unwise to separate the austral forms till actual specimens are available.

Genus Borsonia Bellardi.

All the New Zealand species of this genus have a tiny 2-whorled smooth protoconch, the tip minute, and the second whorl somewhat globular, abruptly ceasing before adult sculpture begins. All have similar columellar plaits—2 in number, very narrow and rather distant, weak at the extremity, higher and sharper within the aperture.

Two generic divisions are represented in New Zealand, one of Surculiform species which seem to be true Borsonia, the other of more Mitromorphoid shells, which may be classed under Cordieria Rouault. The members of the former occur in the Tahuian, Ototaran, and Hutchinsonian, those of the latter are as yet known only from the Tahuian in New Zealand—they seem to agree very well with the shells figured and described by Cossmann and Dall as typical Cordieria.

All the Australian Tertiary and Recent species of this group appear to be true Borsonias. Borsonella Dall and Paraborsonia Pilsbry are unrepresented in New Zealand.

The two divisions as represented in New Zealand may be separated thus:—

Sinus rather deep, sinus area between peripheral keel and strong sutural cord well excavated, so that body whorl appears keeled and tops of axial ribs are hollowed off Borsonia
Sinus shallow and wide, sinus area between peripheral keel and weaker sutural cord hardly excavated, so that body whorl is bluntly keeled and axial ribs diminish regularly on shoulder Cordieria.

Key to Borsonia Species.

(Spiral ornament on all is of same type, i.e., 4 wavy cords between keel and lower suture, the upper two on the keel and separated merely by a groove. Suture margined by a stout swelling increasing in prominence as growth proceeds).

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6-7 axials per whorl, interstices wider zelandica Marshall.
9-10 axials per whorl, interstices subequal.
Shell moderately large (over 15 mm.), spire equal to aperture; axials knobby and squarish on spire whorls, extending over only lower half or less mitromorphoides Suter.
Shell small (under 10 mm.) and much narrower, spire higher than aperture; axials longer and more riblike, extending over lower two-thirds of spire whorls clifdenensis n. sp.

Borsonia clifdenensis n. sp.

Shell rather small, very like Drillia callimorpha Suter in shape. Embryo somewhat worn, but of 1½ smooth whorls, with 1 or 2 closer axials between it and true sculpture. Adult whorls 6, medially carinate, shoulder lightly concave, sloping in below. Nine axials per whorl, reaching from lower suture to half way up shoulder, and nearly down to where base narrows in to canal, interstices 1½ times as wide; only moderately tubercular on keel. A strong swelling with a medial ridge margining suture, shoulder smooth, 4 spirals from keel to suture on spire whorls, about 11 down to canal on body whorl (interstices 2-3½ times as wide), neck of canal with numerous finer and closer spirals. Spire considerably longer than aperture, slender. Sinus Surculiform, moderately deep, growth lines distinct. Fasciole moderately prominent. Pillar with two plaits, rather high up, the lower very weakly developed.

Height, 9 mm.; of spire, 5.3 mm.; width, 3.8 mm.

Locality—Clifden, band 6C (Hutchinsonian).

Type in Finlay collection.

Of the mitromorphoides style, but much smaller, with weaker sculpture and different proportions.

Key to Cordieria Species.

Shell rather slender, spirals thin but fairly prominent, with wider interstices, 2-3 better developed on peripheral keel, about 8 on penultimate whorl—9 axials per whorl huttoni n. sp.
Shell stout and rather squat, spirals thickish, with linear interstices, very low and weak except for 2-3 more prominent on tops of ribs on peripheral keel—
6-7 axials per whorl, very stout and knobby verrucosa n. sp.
9 axials per whorl, shell same shape as above rudis Hutton.
10-12 axials per whorl, shell shorter and wider haasti n. sp.

Cordieria rudis (Hutton). (Figs. 47, 48, 49, 50).

  • 1885. Clathurella rudis Hutton, Trans. N.Z. Inst., vol. 17, p. 328.

  • 1915. Mangilia (Clathurella) rudis (Hutton): Suter, N.Z. Geol. Surv. Pal. Bull. No. 3, p. 39; Pl. 8, F. 14.

  • 1917. Borsonia (Cordieria) rudis (Hutton): Suter, idem., No. 5, p. 84.

This species is restricted to the Tahuian stage, and has not been found elsewhere than at McCulloughs Bridge, where it is, though not

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plentiful, the most common Cordieria. In the coaeval Hampden beds no Cordierias have been found, but one true Borsonia, which genus in turn seems to be absent from McCulloughs Bridge.

Hutton and Suter both confused two species under rudis; Suter selected a holotype from Hutton's five specimens in 1915, but amongst the paratypes were two specimens of the species now separated as haasti.

That four species of Cordieria should occur in the Upper Waihao greensands at McCulloughs Bridge, and none in the lower greensands at the Waihao Downs is remarkable, as Dr. Allan has already noted (Trans. N.Z. Inst., vol. 57, p. 289; 1926).

Cordieria haasti n. sp. (Figs. 57, 58, 59).

Shell small, wide, very squat. Embryo tiny, 2-whorled, mamillate, asymmetrical, the nucleus decidedly lateral. Spire a little lower than aperture, outlines straight, angle about 50 degrees. Whorls short, bluntly sub-medially angled, shoulder a trifle concave, sloping steeply in below. Suture well impressed, wavy, margined by a cord below. 10-12 axials per whorl, knobby and swollen on spire whorls and periphery of body whorl (interstices half as wide), absent on upper half of shoulder, suddenly diminishing below periphery to low narrow ridges persistent down to inception of canal. Whole surface with spiral cords, the strongest margining suture below, 3-4 narrow weak cords on shoulder, 4 strong ribs on remainder of spire whorls and on periphery of last whorl, all these with linear interstices; remainder of last whorl with much weaker, almost flat irregular cords, a trifle stronger and very narrow on canal, interstices of varying width. Aperture sharply pointed and wide above, thence gradually tapering to a short open canal, not notched or truncated. Pillar straight, strongly sloping to left, gently and evenly a little twisted throughout its length. Two parallel gently sloping plaits at upper third of pillar, low, but strong and rather sharp, the upper slightly stronger. Sinus very shallow and gently rounded, situated on shoulder and sutural cord.

Height, 9.5 mm.; of aperture, 5.5 mm.; width, 5 mm.

Locality—Upper Waihao greensands, McCulloughs Bridge (Tahuian).

Type in Finlay collection.

Differs from C. rudis in lower spire, squat shell, closer axials, especially on spiral whorls, and coarser peripheral spirals.

Cordieria verrucosa n. sp. (Figs. 60, 61).

Shell small, shape of C. rudis. Embryo lost. Spire taller than aperture, outlines straight, angle about 35 degrees. Whorls bluntly angled at upper third, shoulder concave, sloping steeply in below. Suture rather hidden, hardly wavy, weakly margined below. Seven axials on last whorl, 8 and 9 respectively on the two preceding; very warty and swollen on spire whorls and periphery of body whorl (interstices of equal width), dwindling regularly and rapidly below periphery, and absent on lower half of base and upper half of

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shoulder. Whole surface with weak spirals, two on periphery stronger and wider apart, the swelling below suture with a median sharp cord, elsewhere (especialy on shoulder); very weak. Aperture pyriform, rapidly attenuated to a very short canal. Pillar, plaits, and sinus as in previous species, but plaits a little lower down.

Height, 12 mm.; of aperture, 5.5 mm.; width, 5 mm.

Locality—Upper Waihao greensands, McCulloughs Bridge (Tahuian).

Type in Finlay collection.

Differs from C. rudis in fewer and more knobby nodules and shorter canal.

Cordieria huttoni n. sp. (Figs. 52, 53, 54, 55).

Shell small, rather slender. Embryo worn. Spire subequal in height to aperture, outlines straight, angle about 30 degrees. Whorls angled at upper third, straight above and below. Suture lightly impressed, faintly wavy, submargined by a narrow cord below. Ten axials per whorl, hardly swollen on periphery (interstices narrower on spire whorls, subequal on body whorl), weak on shoulder and not reaching sutural cord, strong on body whorl to just below top of aperture, thence suddenly vanishing, this point being marked by a second but very weak blunt angulation. Whole surface with narrow rather distant spiral cords (interstices 2-3 times their width); four below shoulder on spire whorls, upper 3 stronger and more distant there and on periphery of body whorl, somewhat irregular on remainder of whorl; hardly any swelling at suture; three cords on shoulder, lower two very weak and faint, uppermost thus rendered prominent, though not stronger than peripheral cords and not really margining suture. Aperture narrowly pyriform, canal short, pillar and sinus as in C. haasti. The type has only one sloping, medial, rather weak plait on the pillar; the sole paratype shows some indication of an extremely weak and distant second plait, almost at top of the pillar.

Height, 8.5 mm.; of aperture, 4 mm.; width, 3 mm.

Locality—Upper Waihao greensands, McCulloughs Bridge (Tahuian).

Type in Finlay collection.

Of more slender habit than the other three species, having fine spiral cords with wide interstices instead of their coarse spirals and sublinear grooves. Very characteristic is the presence of but one distinct plait, much lower down on the pillar than in its congeners.