The Genus Pelicaria in the Tertiary of East Wairarapa
Geological Survey, Wellington.
[Read before the Wellington Branch, June 12, 1952; received by the Editor June 24, 1952.]
Six species of Pelicaria have been collected from Nukumaruan and Waitotaran localities in East Wairarapa. They appear in the following stratigraphic order from lowest to highest: P. mangaoparia n.sp., P. rugosa (Marw.), P. rotunda n.sp., P. acuminata (Marw.), P. media (Marw.) and P. convexa (Marw.).
In the area between the Mangaopari stream and the junction of the Ruakokopatuna and Makara streams five zones may be recognised. Elsewhere, as yet, only two zones have been distinguished.
This paper is an attempt to synthesise some of the results of students who have, in recent years, written theses for M.Sc. about areas in East Wairarapa. Therefore, I have to thank Mr. R. A. Couper and Mr. D. M. McBeath for their permission to use their materials and unpublished results. I take this opportunity to congratulate these people on their excellent work. I am grateful, also, to Mr. C. A. Fleming and Dr. J. Marwick, of the Geological Survey who have allowed me to use their reference collections, have loaned me material and have been ready always with criticism and advice. This paper was written while I was on the staff of the Department of Geology, Victoria University College.
Preliminary Statement of the Geology
Alexander McKay (1878, pp. 16-20, 1879, pp. 81-84) describing the lithological sequence in the Wairarapa district, sub-divided the Upper Tertiary as follows:—
Pliocene: (1) Gravels, fossiliferous sands, lignites, etc.
Upper Miocene: (2) Fossiliferous limestone.
(3) Fossiliferous clays.
(4) Unfossiliferous clays.
Lower Miocene: (5) Fossiliferous clays (Taipo beds).
The two higher divisions of the Upper Miocene of McKay—i.e., (2) fossiliferous limestone and (3) fossiliferous clays, are roughly equivalent to the Onoke Series of L. C. King (1933, p. 336). King considered these beds to be of Nukumaruan age, but more systematic collecting has shown that some of them are probably Upper Waitotaran. King's faunal list from the “junction of the Ruakokopatuna and Makara streams” (King, 1933, p. 338) may have included some fossils from McKay's Pliocene. This formation is particularly well developed in the Huangarua River immediately downstream from the junction of these two streams, is separated from the shell limestones by a conglomerate, and may represent the Lower Castlecliffian.
Detailed lithological sequences of the rocks concerned in the following discussion are shown in the stratigraphic columns, Figs. 1a and 1b. Column (1) is reproduced, with some alterations, from Couper's M.Sc. thesis; column (2) is my own; columns (3) and (4) were provided by McBeath. They illustrate four representative localities.
Fig 1b—Column 3: Stratigraphic column of the Upper Wartotaran and higher beds in the Whakarua and Whangaehu Streams Column 4: Stratigraphic column of the Upper Wartotaran and higher beds on the crest of the Maungaraki Range on the Gladstone-East Coast road
The Upper Tertiary sequence in East Wairarapa as McKay described it is substantially correct, although there are many local variations in the scheme. The series seems to represent a complete cycle of sedimentation, with a wide transgression commencing in Upper Southland times followed by regression in the Waitotaran and Nukumaruan (and perhaps Castlecliffian). The sediments representing the Waitotaran and Nukumaruan are in a general sense progressively coarser from bottom to top, although this change is interrupted at some horizons by sudden reversions to finer grade. These reversions are usually widespread in the Waitotaran and Lower Nukumaruan sediments.
The sedimentary cycle outlined above was accompanied by a minor cycle of folding which commenced at about the same time as the transgression. In the Upper Waitotaran stage there are indications of the quickening of earth-movements and these continued to quicken until the climax of the Kaikoura Orogeny which in this region probably occurred immediately after the Nukumaruan,
It is likely that the Nukumaruan stage is thick beneath the western Wairarapa Plains. But east of the Plains thick Nukumaruan deposits are confined to a narrow strip striking north-east near the western edge of the Maungaraki Range. They thin rapidly towards the crest of the Maungaraki Range where they consist largely of shell limestone. They thin also across the ridges between the (southern) Whangaehu Stream and the Ruamahanga River and greywackes are exposed at several places on these ridges. Greywacke conglomerates occur locally at the base of the Upper Nukumaruan in the Whangaehu Valley, and are the predominant sediments in the uppermost beds. It is argued therefore that the ridge west of the Whangaehu Valley was emergent and the greywacke already exposed even at the time of deposition of the Upper Nukumaruan.
It is clear that in this area during the Nukumaruan there was a well-marked syncline which was forming at an accelerating speed. The axis of the syncline lies approximately along the Whangaehu and Makahakaha streams and continues south-westward through the junction of the Ruakokopatuna and Makara Streams. The syncline is now in part broken by faulting along the western limb, so that it is virtually a fault angle depression at some places.
It is from within the area described above that all our specimens of Pelicaria have been collected. From the nature of the geological history it follows that the physical environment of the Waitotaran and Nukumaruan sea was constantly changing. The water was undoubtedly becoming more and more shallow; and probably it was also becoming more and more land-locked. The changes in the Pelicaria fauna may be due to this more than to any other reason. Another factor likely to produce change of faunas is the fluctuation of warm and cold conditions. C. A. Fleming (1944, pp. 207-220) has shown that the lower Nukumaruan faunas of the East Coast of the North Island are characterised by cold water elements, specially Chlamys delicatulus (Hutt) and this is followed by warmer water faunas in the Upper Nukumaruan. Actually in the Wairarapa region Chlamys delicatulus considerably transcends the Lower Nukumaruan and first appears in beds believed to be Upper Waitotaran, so that its range is somewhat greater here than in Hawke's Bay.
Correlation by the Genus Pelicaria
Six species of Pelicaria have been recognised from Waitotaran and Nukumaruan beds in East Wairarapa; P. acuminata (Marw.), P. media (Marw.), and P. rotunda n.sp. have a wide geographic distribution; P. rugosa (Marw.) is known from two localities, both south of Martinborough; P. mangaoparia n.sp. is definitely known only from the Mangaopari Stream, and P. convexa (Marw.) from a restricted marine facies of uppermost Nukumaruan or perhaps Castlecliffian age near the junction of the Ruakokopatuna and Makara Streams. Some fragmentary specimens in the Waitotaran in the Taueru Valley may be referable to P. mangaoparia.
Five stratigraphic zones can be distinguished in the Mangaopari-Makara area, but only two in the rocks to the north-east, probably in all cases because the facies was unsuited to the existence of the other forms during the period they represent. There is no evidence of any considerable stratigraphic break in the north-
east. The table (Fig. 2) shows that Pelicaria acuminata is restricted in occurrence to an area from the Manga-o-pari to the Te Ahitaitai Stream, and an area on top of the Mangauraki Range near the Gladstone-East Coast Road. P. rotunda occurs more or less universally in the Waitotaran, but in the Nukumaruan is restricted to the areas immediately east of the Whangaehu River and north of the Ngarara Stream. Apparently Pelicaria acuminata preferred a shallower environment, since it occurs in a rather coarser facies than Pelicaria rotunda and is distributed more or less around the edges of the main basin of deposition. The geographic and stratigraphic relations of the two species are discussed in the section on systematics.
Since P. rugosa and P. mangaoparia have not been found in the Whakarua area the downward limit of P. rotunda there is not definitely established. The lowest occurrence known is 500 feet below the top of the Waitotaran, which reaches in all something over 1000 feet. In the Mangaopari Stream one specimen has been collected from loc. V.301, high in the P. mangaoparia zone, but none lower.
The zones distinguished are tabulated as follows:—
|Mangaopari area||Whakarua etc.|
|Upper Nukumaruan||P. convexa|
|P. media||P. media|
|Lower Nukumaruan||P. acuminata|
|P. rugosa||P. rotunda|
|High Waitotaran||P. mangaoparia|
The beds included in these zones are shown on each of the stratigraphic columns 1—4 figs. 1a, 1b.
The occurrences of other fossils in these rocks have not yet been sufficiently analysed to cite with confidence additional index forms for each zone, but the
following remarks summarise what is known of the range of the most important of them.
Chlamys delicatulus (Hutt.): At the junction of the Ruakokopatuna and Makara Streams specimens have been found at the top of P. media zone, but to the north it has been found no higher than the middle part of this zone. In the Mangaopari Stream it appears first at the same horizon as P. rugosa. In the north it appears first at about the base of the Nukumaruan, but in the Ngarara-Whakarua area it may have been absent in the Upper Waitotaran owing to unfavourable ecological conditions.
Austrofusus cottoni King: So far this species has been collected only from the P. media zone.
Austrofusus aff. chathamensis Finlay: Known from the P. media zone in the Ngarara Stream and also in the Makahakaha Stream.
Aeneator imperator King: Appears to be confined to the P. rugosa and P. acuminata zones.
Zephos onokeana King: This species occurs in the zone of P. rugosa in the Mangaopari Stream, between localities V303 and V305, the latter being probably basal Nukumaruan. It occurs with P. aff. acuminata in mudstones on the Taueru Road a little west of the Taueru Hotel, the rocks here being near the Waitotaran-Nukumaruan boundary. McBeath has collected it with Z. tuturewa Fleming in the Waitotaran mudstones immediately underlying the Lower Nukumaruan shell limestone (Maungaraki Fmtn.) on the Gladstone East Coast Road. I have not yet had the opportunity to collect from the cliffs east of Lake Ferry, the type locality of Z. onokeana. The list of L. C. King (1933, p. 337) suggests that he has lumped together faunas from some thickness of rocks, representing both the Waitotaran and the Nukumaruan stages. I believe Z. onokeana ranges from the uppermost Waitotaran to the lowermost Nukumaruan and it may be used as a rough index form for the P. rugosa zone.
Aoteadrillia: This genus is represented by several species which are not yet adequately defined. A. beta (King) and A. alpha (King) seem to be confined to the P. mangaoparia and P. rugosa zones. Above this I think they are replaced by A. gamma (King). The ranges of these might be better established after a zonal collection of the type locality (the cliffs east of Lake Ferry). A. trifida Powell, A. bisecta Powell and A. gamma are probably all restricted to the Lower Nukumaruan. In the Upper Nukumaruan (P. media zone) there are many varieties, but all apparently allied to A. wanganuiensis (Hutt) and A. chordata (Suter).
The holotypes of the two following new species will be placed in the Geological Survey collection.
Pelicaria mangaoparia n.sp. Plate —, figs. 8, 9, 10.
[The section below cannot be correctly rendered as it contains complex formatting. See the image of the page for a more accurate rendering.]
Shell small, about the same size as P. media (Marw.), spire slightly higher than the aperture. Whorls 6 1/2, first smooth and much smaller than the first whorl in P. acuminata. Upper whorls slightly more depressed than the lower, giving spire an over-all slightly convex aspect. Sculpture 7 to 8 fine spiral lirae appear on second whorl, increasing to full strength on the third. Bicarination starts on the later part of the third whorl (though this is not quite constant in paratypes) Two strong cinguli are present on the fourth whorl. A narrow flat shoulder is
Fig. 1,-3.—Pelicaria cf. media (Marw.) cf. acuminata size. (M
Fig. 2.—pelicaria aff. media (Marw.) aff. rotunda. n. sp.
Fig. 4.—Pelicaria media (Marw.).
Figs. 5, 7.—Pelicaria rotunda n.sp. Holotype (5) and paratype.
Fig. 6.—Pelicaria cf. acuminata (Marw.) cf. rotunda n. sp.
Figs. 8, 9, 10.—Pelicaria mangaoparia n.sp. Holotype (9) and paratypes (8 and 10).
Fig. 11.—Pelicaria acuminata (Marw.) Topotype.
present even on the second whorl, separated from the lower part of the whorl by a distinct, broad angle in whorls three and four; this angle narrowed to about 90° by the growth of a strong spiral cord on the fifth and sixth whorls. This cord corresponds in position to the uppermost cingulus of P. acuminata, but is not nearly so strong, the holotype having it stronger than is usual in paratypes. The body whorl has three rather narrow, raised, rounded cinguli, the median slightly weaker than the others. Beneath these three is a fourth obsolescent cingulus, much lower and weaker; on the base four widely spaced, thin, distant, spiral cords, regularly decreasing in strength from the highest to the lowest, which is very weak. Paratypes usually have only three cords on the base. The entire shell covered by weak but distinct spiral lirae. Blunt, low tubercles are present on the uppermost cingulus (about 18–20 per whorl) and sometimes on the median cingulus. In some paratypes the tubercles are very weak.
Dimensions. Height, 35 mm. Diameter, 23 mm.
Localities. V.300 type and one other; V.301 two specimens; V.34 one specimen. G.S.2626, 4 specimens.
Remarks. The type has been selected as the best preserved specimen available. In some respects it represents a slightly atypical modification of the species. The whorl is more quadrate than in some paratypes which have rather convex whorls. The spiral lirae are less strongly developed, the cinguli are narrower, and the lowest stronger, than in some paratypes.
In aspect the shell is between acuminata and rotunda. The holotype and some paratypes are more nearly allied to the former species, other paratypes (with convex whorls, broader cinguli and stronger spiral lirae) are closer to P. rotunda. The specimens nearer acuminata frequently have slightly higher spires—e.g., the type, 35 mm. × 23 mm., while specimens nearer rotunda tend to have a more depressed spire—e.g., a paratype 33 mm. × 23 mm.
Because of this intermediate character and also because of its stratigraphic position P. mangaoparia is thought to be possibly the stock from which P. acuminata and P. rotunda diverged. From its broad cinguli P. rotunda may, however, be more nearly related to P. canaliculata (Zitt).
Pelicaria rotunda n.sp. Plate —, figs. 5 and 7.
[The section below cannot be correctly rendered as it contains complex formatting. See the image of the page for a more accurate rendering.]
Shell lower than acuminata but much broader, proportions more like those of media; spire same height as aperture. Whorls 6, first three quite convex, later three with a flat (not channelled) shoulder, but with sides still fairly convex; on body whorl, which is very broad, the convexity continuing over the base without any angulation at the periphery. Sculpture: First 1 1/2 whorls smooth, then developing about 10 fine spiral threads; on latter part of third whorl two broad ribs appear, increasing in strength on fourth whorl to two low, slightly rounded, broad cinguli, slightly narrower than the interspace. On body whorl a third cingulus is present at level of suture, somewhat broader and less raised than the other two, though this is not always so in paratypes. On the base is a very obsolescent cingulus which is better developed in paratypes but never very strong. The spiral lirae continue to be well developed over the whole shell except on the flattened shoulder where they are obsolescent.
In each of the grooves between the three main cinguli is a strong spiral thread. The upper of these is seen to arise on about the fourth whorl, by the strengthening of one of the spiral lirae. Numerous small nodules are present on the cinguli
(specially on the upper) of the fourth whorl, and these increase in strength to blunt low tubercles and become rather widely spaced on the fifth and body whorls (16 on body whorl of holotype, 16–20 on paratypes). Base ornamented with 8 fine, distant spiral cords. Some paratypes have fewer than eight, and stronger cords on the base.
Dimensions. Height, 43 mm. Diameter, 30 mm.
Localities. V.205 (holotype and 27 paratypes); V.7, V.25, V.59, V.204, V.216, V.272, V.274, V.278.
Remarks. P. rotunda is distinguished from P. acuminata by its relatively depressed spire, weaker, broader and tuberculate cinguli, stronger spiral lirae, more numerous spiral cords at the base, and the unchannelled or only slightly channelled shoulder.
Immature specimens of P. rotunda are very similar to P. media, but can be distinguished by the fact that corresponding whorls on rotunda are much larger, there are more initial spiral threads, usually rather narrower cinguli, and the tubercles are more strongly developed than on media, and appear earlier (third to fourth whorl on rotunda, fifth whorl on media). Mature specimens are much larger than media and rarely have the suture even slightly channelled (channelling is rather inconsistent in media however.)
Pelicaria rotunda is a very unstable species, giving many varieties most of which probably occur locally only. At present none of the varieties seem to be worth naming, but a few of the most noteworthy may be mentioned.
(a) Localities V.59 one specimen and V.216 (see Fig. 7, Plate —) one specimen: Pelicaria rotunda typical in all respects except that a heavy cord occupies each of the spaces between the three main cinguli. Each of these cords arises by enlargement of one of the spiral lirae, at about the fourth whorl.
(b) Localities V.274, 1 specimen and V.7, 1 specimen: As above, but with only one cord, between the two lower cinguli.
(c) Locality V.204: There are 4 specimens of typical P. rotunda. Besides there is one specimen in which the sculpture is obsolete, except the spiral lirae, and the whorls are convex, giving a form very like P. convexa. It lacks the flattened border to the suture on the earlier whorls and the channelling on the body whorl, and it has fewer and weaker spirals than convexa. One other specimen is intermediate between this extreme variation and the true P. rotunda.
(d) The number and strength of the spiral cords on the base is a variable feature, but there are rarely less than five cords, and rarely more than eight. They may be little more than threads or they may be quite heavy.
The convexa-like adaption of P. rotunda is from beds at about the middle of the Lower Nukumaruan. It is not suggested that P. convexa diverged at this early time, but that P. rotunda had a tendency (or capacity) to lose its heavy ornament, and very probably was the stock from which P. convexa eventually arose.
Intermediate forms between P. rotunda and P. media occur at the base of the P. media zone (see remarks under P. aff. media) which are taken as definite evidence that P. media is descended from P. rotunda.
It might also be indicated here that P. rotunda seems to be the species most closely related to P. vermis (Martyn) and Pelicaria tricarinata (Lesson).
Pelicaria media might be thought equally close but its smaller size is against this. Besides, Pelicaria media, unlike rotunda, seems to have been a comparatively stable species, not disposed to change.
The stratigraphic and geographic relations of P. rotunda and P. acuminata are rather involved, as a glance at the table (Fig. 3) will show. Once specimen of P. rotunda (none of acuminata) was found in the higher part of the P. mangaoparia zone. Both rotunda and acuminata have been collected from various horizons in the P. rugosa zone, but above this only P. acuminata occurs in the Mangaopari and Makara Streams. In the area from the Whakarua Stream northwards on the other hand P. acuminata is not known, and P. rotunda ranges from the Upper Waitotaran to the top of the Lower Nukumaruan.
On the crest of the Maungaraki Range Pelicaria acuminata occurs together with forms intermediate between P. acuminata and P. rotunda in the silts between the middle and upper limestones (see column 4). The facies at this locality has more in common with that in the Mangaopari and Makara Streams than with that in the Te Ahitaitai and Whakarua Streams.
Between the Mangaopari and Whakarua areas, that is in the valleys of the Ngarara and Te Ahitaitai streams, faunas from the base to near the top of the Lower Nukumaruan include fairly typical specimens of Pelicaria rotunda together with forms intermediate between P. rotunda and P. acuminata. These intermediate forms have the high spire of acuminata, and often have narrow, raised cinguli, but the body whorl is grossly enlarged and convex, the nodules are strongly developed on the cinguli, and the base has from 5 to 8 spiral cords. Only one specimen that could be regarded as a typical P. acuminata was collected, this from V.14, the concretionary sandstone (basal Nukumaruan) in the South Branch of the Ngarara Stream. Most of the acuminate specimens come from near the base of the Nukumaruan, that is near the concretionary sandstone and Chlamys delicatulus shell-bed, which are thought to indicate shallowing of the sea in this area. It would appear that here the two distinct faunas represented to the north and south have mingled and interbred to form a hybrid swarm. This implies that they are closely related forms.
From the distribution of the two species as outlined above it is judged that P. acuminata lived in shallow waters near the shore, as is indicated by the facies in the Mangaopari and Makara Streams and on the Maungaraki Range; while P. rotunda preferred a deeper water environment, being now found in the silty mudstones in what must have been (from the structural evidence) the centre of the basin of sedimentation in lower Nukumaruan and late Waitotaran times.
Being thus restricted to different habitats P. rotunda and P. acuminata might be considered no more than ecological varieties of the same species. However, the essential differences between the two—i.e., the ratio of height to diameter, and the sculptural differences, are marked and constant where the two forms are living separated from each other. In both these features each species is more closely related to P. mangaoparia than to each other. The cinguli of P. rotunda, by their broadness, suggest a possible relationship with P. canaliculata (Zittel). The tubercles on the cinguli, the development of spiral lirae and the non-channelled shoulder, however, show that P. rotunda is far removed from P. canaliculata. It is most probably evolved from P. mangaoparia or some other form close to it. The probable phylogenetic relationships of P. acuminata and P. rotunda are summarised in Fig. 3.
If this phylogenetic relationship is valid P. rotunda and P. acuminata are not simply varieties but must be regarded as different species, evolving along different phylogenetic lines, though closely related through a common ancestor not far removed.
Pelicaria rugosa (Marw.)
1926. Struthiolaria rugosa Marwick. Trans. N.Z. Inst., vol. 55, p. 189, Pl. 13, fig. 2.
Pelicaria rugosa ranges through about 300 feet of beds in the Mangaopari Stream. Specimens agree well with Marwick's description, except that they usually have 7 or 8 spiral cords on the spire whorls.
Localities. V.302, V.304, G.S.2624 (all the Mangaopari Stream); V.294, new cutting on Awhea Road, three miles south of Martinborough.
Pelicaria acuminata (Marw.) Plate —, fig. 11.
1926. Struthiolaria acuminata Marwick. Trans. N.Z. Inst., vol. 55, p. 185, Pl. 15, figs. 11, 12.
The name should be kept for forms with the high, turreted spire notably longer than the aperture, and with five high, narrow cinguli, smooth or very weakly nodulous, on the body whorl, 3 to 5 moderately strong spiral cords on the base, and the body whorl not grossly enlarged.
Localities. V.260 Maungaraki Range, Gladstone East-Coast Road; V.14 Ngarara Stream (South Branch); G.S.2904, V.306, G.S.2610, G.S.2611, G.S.1612, all in Mangaopari and Makara Streams.
Pelicaria media (Marw.). Plate —, fig. 4.
1926. Struthiolaria media Marwick. Trans. N.Z. Inst., vol. 55, p. 187, Pl. 15, figs. 13, 14.
The type is from Castlepoint (Nukumaruan), a shell about half the size of P. rotunda, with depressed, pointed spire, low, rounded broad cinguli, and spiral threads of varying strength over most of the shell. Many specimens corresponding closely in size and general form to the type, have been collected from a zone occupying the lower part of the Upper Nukumaruan. They vary to some extent in the strength of the cinguli, which may also be either slightly nodular or smooth; the flattened border to the suture may be broad, when the sides of the whorls are
nearly flat, and vertical or narrow, when the sides are strongly convex. The suture is often slightly channelled on the body whorl. There is some variation in the size, but no specimens are known to the writer that approach P. rotunda in size.
The name P. media should be kept for these small shells with broad, rounded cinguli and narrow interspaces. It is a stable and fairly specialised form, and died out after a very brief period, probably without any descendants.
Localities. V.3, V.10, V.12, V.13, V.4, V.6, V.11, V.24, V.203, V.207, V.208, V.247, V.255, G.S. 2613.
Pelicaria aff. media (Marw.)
At the base of the P. media zone, in the Makara, Ngarara, Te Ahitaitai and Whakarua streams, specimens intermediate in character between P. rotunda and typical P. media have been collected. Most of these have sculpture more or less like media, but are not much smaller than P. rotunda (see fig. 2, Pl. —, a specimen from V.1, sands and shell beds below the lower shell limestone, Te Ahitaitai Stream).
More complex relationships are exhibited by forms from the lower Makara River. From G.S.2613 are four specimens, one a typical media. The other three have the sculpture characteristic of P. media but have the spire elevated in a fashion reminiscent of P. acuminata (Fig. 1, Pl. —). From V.307, a horizon slightly lower than G.S.1613, are two specimens with the spire only slightly acuminate, with the numerous cords on the base, and well developed spiral lirae of P. media, but narrow cinguli like P. acuminata (Fig. 3, Pl. —).
If the writer's earlier conclusions, concerning the phylogeny of the group are correct, the only explanation of this acuminate variety of P. media is that when it first invaded the area the species hybridised with P. acuminata which was previously established there. Subsequently it might have taken some time for the acuminata strain to breed out of the community inhabiting the Makara area.
Localities. G.S.2613, V.307, V.3, V.1, V.275.
Pelicaria convexa (Marw.)
1926. Struthiolaria convexa, Marwick. Trans. N.Z. Inst., vol. 55, p. 188, Pl. 15, Figs. 3, 4.
One broken specimen, of the spire whorls only, was collected from V.311, above the Pelicaria media zone at the junction of the Ruakokopatuna and Makara Streams. It agrees well with Marwick's description and figures.
The beds of the P. convexa zone are separated from those of the P. media zone by a conglomerate which might represent a fairly long period. The P. media zone is almost certainly Upper Nukumaruan. The P. convexa zone, therefore, may be part of the Castlecliffian.
Since this paper was written further material has become available. Typical specimens of P. acuminata have been collected from the Lower Nukumaruan in the region around the Taueru River by Mr. D. Campbell, Honours student at Victoria University College. The sediments at this locality are chiefly sandstones and siltstones and are comparatively thin.
P. rugosa has been collected by Mr. R. L. Kite, of V.U.C., from the cliffs east of Lake Ferry at a horizon probably fairly low in the Nukumaruan.
No mention has been made of P. fossa (Marw.). This species was recorded by L. C. King (1933, p. 339) from the junction of the Gladstone-Martinborough and Hinakura Roads, and P. cf. fossa from the junction of the Ruakokopatuna and Makara Streams. No specimens referrable to this species have since been collected from these localities and none of King's specimens are present in his collection at Victoria University College. It seems best, therefore, to delete P. fossa from the faunal lists of the two localities concerned.
Key to Locality Numbers
A.—Victoria College Locality Numbers
V.1.—N166/516, Huangarua S.D., 150 chains at 289° from Trig R5. Te Ahitaitai Stream 10 to 20 chains upstream from junction with Whangaehu River. Sands and shell beds below lower shell limestone.
V.3.—N166/501, Huangarua S.D., 146 chains at 273° from Trig R5. Te Ahitaitai Stream 30 chains upstream from Whangaehu junction. Lowest 30 feet of silts overlying lower shell limestone.
V.4.—N166/502, Huangarua S.D., 148 chains at 280° from Trig R5. Te Ahitaitai Stream 30 chains upstream from junction with Whangaehu River. Lower shell limestone.
V.6.—N166/519, Huangarua S.D., 215 chains at 272° from Trig R5. Whangaehu River 2 to 3 chains north of junction of Ngaiara Stream.
V.7.—N166/520, Huangarua S.D., 107 chains at 273° from Trig R5. 60 chains up stream joining Te Ahitaitai 28 chains from its junction with Whangaehu River.
V.10.—N166/521, Huangarua S.D., 200 chains at 264° from Trig R5. East bank of Ngarara Stream, 10 chains south of junction of Martinborough-Hinakura and Gladstone roads.
V.11.—N166/504, Huangarua S.D., 210 chains at 263° from Trig R5. Ngaraia Stream, sharp bend 22–24 chains south of junction of Martinborough-Hinakura and Gladstone roads.
V.12.—N166/522, Huangarua S.D., 194 chains at 268° from Trig R5. Junction of Martinborough-Hinakura and Gladstone roads.
V.13.—N166/505, Huangarua S.D., 175 chains at 280° from Trig R5. Sharp bend on Gladstone road, 40 chains south of Te Ahitaitai Stream.
V.14.—N166/506, Huangarua S.D., 120 chains at 070° from Trig Windy Peak. Fifty chains up south branch of Ngaiaia Stream. Muddy silts interbedded with hard concretionary sandstone.
V.24.—N166/529, Huangarua S.D., 70 chains at 118° from Trig Oyster. Gladstone road 46 chains north of junction of Te Ahitaitai Stream with Whangaehu River. Silts overlying lower shell limestone.
V.25.—N166/530, Huangarua S.D., 116 chains at 300° from Trig R5. Fifty chains up small creek joining Te Ahitaitai about 3 chains upstream from its junction with the Whangaehu River. Collected Vella, 1949.
V.34.—N165/501.—Waipawa S.D. Small creek leading into well marked cut-off meander on east side of Awhea Road, approx. 14 chains south of turn off into Birch Hill Station. Blue-grey mdst., 200 feet below Chlamys delicatulus shell bed. Coll. Couper, 1948.
V.59.—N166/540, Huangarua S.D., 52 chains at 274° from Trig R5. Ninety-five chains up stream joining Te Ahitaitai Stream, 30 chains from its junction with Whangaehu River; (about 38 chains upstream from N166/520). Sands and muddy silts overlying thin concretionary sandstone. Collected Vella, 1949.
V.203.—N162/517, Huangarua S.D., 217 chains at 247° from Trig R7. Grid Ref.: 057.301; 95 chains down Whangaehu River from junction with Whakarua Stream. Collected McBeath, 1949.
V.204.—N162/518, Huangarua S.D., 138 chains at 253° from Trig R7. Grid Ref.: 072.311; 20 chains up Whakarua Stream. Collected McBeath, 1949.
V.205.—N162/519, Huangarua S.D., 134 chains at 250° from Trig R7. Grid Ref.: 073.310. Junction Whakarua Stream and first tributary coming from south, about 25 chains from junction of Whakarua Stream and Whangaehu River. Collected McBeath, 1949.
V.207.—N162/520, Huangarua S.D., 162 chains at 265° from Trig R7. Grid. Ref.: 066.316. 25–27 chains up Whangaehu River from junction of Whakarua Stream. Collected McBeath, 1949.
V.208.—N162/521, Huangarua S.D., 161 chains at 267° from Trig. R7. Grid Ref.: 066.318. 35 chains up Whangaehu River from junction with Whakarua Stream. Collected McBeath, 1949.
V.216.—N162/529, Huangarua S.D., 56 chains at 107° from Trig R10. 5 chains down Oreka Stream from junction with small tributary which runs in valley between E and F trigs. Collected McBeath, 1949.
V.247.—N162/560, Huangarua S.D., 178 chains at 253° from Trig R7. 30 to 34 chains down Whangaehu River from junction with Whakarua Stream. Grid Ref.: 064.308. Collected McBeath, 1949.
V.255.—N162/568, Huangarua S.D., Grid Ref: 064.309. 20 to 28 chains down Whangaehu River from junction with Whakarua Stream. Collected McBeath, 1949.
V.260.—N162/501, Wainuioru S.D., 17 chains at 297° from Trig Pukerua Grid Ref.: 168.359. Admiral Road 0 to 4 chains south of saddle where road crosses ridge near Pukerua Trig. Collected McBeath, 1949.
V.272.—N162/584. Huangarua S.D., 72 chains at 229° from Trig R7. Grid Ref.: 089.310. 119 chains along Whakarua Road just below farmhouse near bridge where Whakarua Road crosses Whakarua Stream. Collected McBeath, 1949.
V.274.—N162/586, Huangarua S.D., 92 chains at 239° from Trig R7. Grid Ref.: 084.309. 92 chains along Whakarua Road. Collected McBeath, 1949.
V.275.—N162/587, Huangarua S.D., 132 chains at 280° from Trig R7. Grid Ref.: 072.325. Whangaehu Valley Road, 100 chains south of junction with Mahapuka Road. Road descends into small gully. Collected McBeath, 1949.
V.278.—N162/590, Huangarua S.D., 39 chains at 093° from Trig R10. Grid Ref.: 115.402. 65 chains up Oreka Stream, in right bank where stream changes its direction from N.E. to S.E. Collected McBeath, 1949.
V.294.—N162/506, Huangarua S.D., 14 chains at 105° from Trig Harris. New cutting on Awhea Road 236 chains south of Martinborough. Collected Couper and Vella, 1950.
V.300.—N165/509, Waipawa S.D., 104 chains at 208° from Trig Point Range. Mangaopari Stream, cliffs on S.W. side 40 chains upstream from junction with Makara. Collected Couper and Vella, 1950.
V.301.—N165/510.—Waipawa S.D., 95 chains at 217° from Trig Point Range. Mangaopari Stream 24 chains upstream from junction with Makara River. Collected Couper and Vella, 1950.
V.302.—N165/511, Waipawa S.D., 94 chains at 222° from Trig Point Range. Mangaopari Stream 20 chains upstream from junction of Makara. Collected Couper and Vella, 1950.
V.304.—N165/513, Waipawa S.D., 84 chains at 222° from Trig Point Range. Awhea Road, opposite ford over Mangaopari Stream leading to Birch Hill homestead. Below 100 foot shell limestone. Collected Couper and Vella, 1950.
V.305.—N165/514, Waipawa S.D., 81 chains at 225° from Trig Point Range. Awhea Road 2–3 chains north of V.304, between 2 shell limestones. Collected Couper and Vella, 1950.
V.306.—N165/515, Waipawa S.D., 70 chains at 244° from Trig Point Range. Makara River, immediately west of Te Awaite cutting, 26 chains below junction of Mangaopari Stream. Collected Couper and Vella, 1950.
V.307.—N165/516, Waipawa S.D., 46 chains at 309° from Trig Point Range. Makara River. 18 chains up stream from junction with Ruakokopatuna River. Collected Couper and Vella, 1950.
V.311.—N162/520, Waipawa S.D., 76 chains at 322° from Trig Point Range. Huangarua River, 5 chains downstream from junction of Ruakokopatuna and Makara Streams. Collected Couper and Vella, 1950.
B.—Geological Survey Locality Numbers
G.S.2610.—Sandy mudstone, Makara Stream, about 50 chains upstream from Ruakokopatuna junction, outerop forming west side of stream opposite large slip. Waipawa S.D.J. Marwick and M. Ongley No. 1, 31/1/1941.
G.S.2611.—Sandy mudstone, Makara Stream about 40 chains upstream from Ruakokopatuna junction, east bank of stream just south of sharp bend at long high cliff. Waipawa S.D.J. Marwick and M. Ongley No. 2, 31/1/1941.
G.S.2612.—Sandy mudstone east bank of Makara Stream. 30–35 chains upstream from Ruakokopatuna junction. Waipawa S.D.J. Marwick and M. Ongley No. 3, 31/1/1941.
G.S.2613.—Sandy mudstone east bank of Makara Stream, 18 chains upstream from Ruakokopatuna junction. Waipawa S.D.J. Maiwick and M. Ongley No. 4, 31/1/41.
G.S.2624.—Sandy mudstone 100–150 feet below 100 feet limestone roadside half-way down hill at Makara-Mangaopari junction. Waipawa S.D.J. Marwick and M. Ongley. No. 19, 1/2/1941.
G.S.2626.—Sandy mudstone with concretions and Pelicaria 6 chains up Mangaopari from Makara junction. Waipawa S.D.J. Marwick and M. Ongley, 1/2/1941.
G.S.2904.—Blue sandy mudstone below limestone above road. Hillside east of Mangaopari-Makara junction about same as 2623 and 2624. Waipawa S.D. H. W. Wellman.
List of References
Couper, R. A., 1948. The Geology of the Makara and Ruakokopatuna Valleys, East Wairarapa. Univ. of N.Z. Thesis (Lodged in Victoria University Coll. Library).
Fleming, C. A., 1944. Molluscan Evidence of Pliocene climatic change in New Zealand Trans. Roy. Soc. N.Z., vol. 74, Pt. 3, pp. 207–220.
King, L. C., 1933. Tertiary Molluscan Faunas from the Southern Wairarapa. Trans. N.Z. Inst., vol. 63, Pt. 3, pp. 334–354.
McBeath, D. M., 1950. The Geology of an Area North-East of Martinborough, East Wairarapa. Univ. of N.Z. Thesis (lodged in Victoria University Coll. Library).
MoKay, A., 1878. Report on East Wairarapa District. Rep. Geol. Explor. 1877–78, no. 11, pp. 14–24.
— 1879. The Southern Part of the East Wairarapa District. Rep. Geol. Explor. 1878–79, no. 12, pp. 75–86.
Mabwick, J., 1924. The Struthiolaridae. Trans. N. Z. Inst., vol. 55, pp. 161–190.
Vella. P., 1949. The Geology of an Area South-East of Martinborough. Unv. of N.Z. Thesis (lodged in Victoria Univ. Coll. Library).