A Revision of the Recent Scaphopod Mollusca of New Zealand By R. K. Dell [Received by the Editor, March 14, 1956.] Abstract The number of valid species of scaphopod mollusca recorded from New Zealand is 13, three belonging to the family Siphonodentaliidae, and 10 to the family Dentaliidae, Dentalium huttoni Kirk and D. marwicki Mestayer are shown to be synonyms of D. nanum Hutton. Keys for the differentiation of all species and full distributional data are given. All the species are endemic to New Zealand waters. Introduction The recent New Zealand Scaphopoda have not been revised since Suter's account in the Manual of New Zealand Mollusca (1913). The number of species concerned is not large, yet knowledge of the fauna has only been slowly gained. Mestayer described a new species, Dentalium marwicki, in 1926, while Finlay in the same year was the first to show that our common Cadulus was not the same as an Australian form, and pointed out the peculiar apical features. Dell (1953) described two new deep water species. Miss M. K. Mestayer amassed a collection of recent Scaphopods which is now in the Dominion Museum. Dredgings carried out in several parts of New Zealand in recent years have considerably added to this collection, and the writer has had access to the Suter Collection by courtesy of Dr. C. A. Fleming. Mr. N. Gardner has kindly lent material for the purpose of this revision. The Scaphopod material obtained by the Chatham Islands Expedition, 1954, has also been treated here for the sake of completeness, as has that obtained in shallower water (under 610 metres) by the Galathea Expedition. Family Siphonodentaliidae Genus Cadulus Philippi 1884 Type species of the genus (monotypy) Dentalium ovulum Philippi, Recent, Southern Italy. Until the apical characters of many more species are adequately known no soundly based division into subgenera is possible. The existing divisions to which the New Zealand forms appear to be most closely related are mentioned under each species. Neither of the two common shelf forms, teliger nor delicatulus, fits into any existing subgeneric unit easily, nor are they closely related to one another. Key to New Zealand Species of Cadulus 1 (2) Shell considerably swollen near aperture, length 15 mm… colubridens Watson. 2 (1) Shell fairly evenly tapered, slightly constricted near aperture mm… 3. 3 (4) Apex with 6 slits, shell up to 13.5 mm in length mm… delicatulus Suter. 4 (3) Apex with raised triangular process on convex side, shell up to 5.0 mm in length mm… teliger Finlay. Cadulus delicatulus Suter 1913, Text-figs. 11, 12. 1913. Cadulus delicatulus Suter. Man. N.Z. Moll., p. 823, Pl. 32 f. 7. This species, which proves to be quite common in depths from 11 to 330 fathoms, was not described until 1913. Suter gave no details of the peculiar apical characters. There is a deep narrow slit on each side. Ventrally there is a shallow slit which

divides the ventral margin into two lobes. Dorsally there is a single central shallow slit, and on each side a deeper, wide slit so that the dorsal margin is cut into four teeth. Six slits and teeth are unusual in Cadulus, the usual number in those species which have slit apices being two or four. Cadulus dalli Pilsbry and Sharp from off Patagonia and Magellan Strait has a similar arrangement, but only five teeth (three teeth along the dorsal margin). Cadulus parisiensis Deshayes from the Paris Basin has the margins cut into three and five teeth respectively with a similar deep indentation on each side. These species may all be included in the subgenus Polyschides Pilsbry and Sharp. Radula (Fig. 7) with five teeth in a row. Central teeth approximately as high as wide, cutting surface irregularly shaped but usually with small cusp on each outer corner, central edge rounded. Laterals with deep bases. Localities. Recent: 23 fathoms off Ahipara (Dell Coll.); off Flat Point, east coast of North Island (Bollons Collection); B.S. 103, off Pickersgill Island, Queen Charlotte Sound, in 10 fathoms; B.S. 128, Tennyson Inlet, Pelorus Sound, 12–15 fathoms, W. H. Dawbin, 26.12.1951; off Takaka, Nelson; Chatham Island Exped. St. 4, Chatham Rise 43° 14′ S., 176° 11′ E. in 200 fathoms; Chatham Island Exped St. 5, Chatham Rise, 43° 32′ S., 178° 38′ E. in 300 + fathoms; Chatham Island Exped. St. 59, Chatham Rise, 43° 48′ S., 177° 19′ W. in 290 fathoms; Chatham Island Exped. St. 41, S.E. of Pitt Island, Chatham Islands, 44° 35.5′ S., 176° 04′ W. in 338 fathoms. Galathea Stations 603, 608–611, 613, 615–619, all in Milford Sound in depths between 30 and 305 metres. Galathea Station 633, between Wellington and Auckland, 39° 15′ S., 178° 00′ E. in 83 metres. New Golden Hind Stations 3, 23, 25, 35, 37, 39, 43, 44, 45, 46, 51, 54, 55, 58, 75, 80, 81, 83 (see Fleming, 1950, p. (5) 30), varied localities in Preservation Inlet, Chalky Sound, Edwardson Sound, Cunaris Sound, Dusky Sound, Breaksea Sound and Daggs Sound, Fiordland in depths between 11 and 58 fathoms. Caswell Sound in 30 fathoms, R. K. Dell, 23.3.1949. Fossil: Kai Iwi (ex Marshall Collection) Greatest Diam of Diam. of Length Diam. Aperture Apex Arc mm mm mm mm mm Type 11.5 1.8 1.5 0.7 0.9 Paratype 10.1 1.6 1.6 0.6 0.7 Pickersgill Island 12.2 1.9 1.7 0.7 0.8 Pickersgill Island 11.0 1.8 1.6 0.9 0.5 Pickersgill Island 9.8 1.7 1.6 0.9 0.5 Takaka 13.5 2.1 2.0 1.0 0.9 110 fathoms off Great Barrier 13.2 1.7 1.4 0.8 0.9 C.I.E. St. 41 11.0 1.7 1.4 0.8 0.8 C.I.E. St. 41 10.5 1.8 1.5 0.9 0.5 C.I.E. St. 41 11.0 1.9 1.7 1.0 0.7 Cadulus teliger Finlay, 1926. Text-fig. 23. 1904. Cadulus spretus Hedley (non Tate and May), Rec. Austral. Mus. vol. 5, p. 89. 1908. Cadulus spretus Suter (non Tate and May), Trans. N.Z. Inst., vol. 40, p. 353. 1926. Cadulus teliger Finlay, Trans. N.Z. Inst., vol. 57, p. 444, Pl. 19, figs. 53–54. The peculiar apex of teliger Finlay does not agree with any named subgenus unless it can be regarded as an abnormal Dischides in which the two slits have disappeared, but the portion cut off by them has remained as the peculiar raised isosceles triangle of teliger (Fig. 15). It is best retained in the meantime in Cadulus (s.l.) Localities: 15 miles south of Big King Island, in 98 fathoms; off North Cape, in 75 fathoms, J. A. Bollons; off Hen and Chickens Island, in 26–30 fathoms, J. A. Bollons; off Cuvier Island, in 27–40 fathoms, J. A. Bollons; 3 miles N.E. of Channel.

Text-fig. 1.—Figs. 1, 2.—Apices of two specimens of Dentalium zelandicum (Sowerby). Fig. 3.—General, lateral and marginal teeth of radula of Dentalium suteri Emerson. Fig. 4.—Central, lateral and marginal teeth of radula of Dentalium zelandicum (Sowerby). Figs. 5, 6.—Enlarged outlines of lateral teeth of Dentalium zelandicum (Sowerby). Fig. 7.—Central, lateral and marginal teeth of radula of Cadulus delicatulus Suter. Island, Hauraki Gulf, in 26 fathoms, J. A. Bollons; B.S. 178 off Yorke Bay, Wellington Harbour, in 9 fathoms, 31.5.1953; Rangitoto Passage, Durville Island, in 20 fathoms; Queen Charlotte Sound, 16–18 fathoms, Captain Bolton; B.S. 101, off White Rocks, Queen Charlotte Sound, in 25 fathoms; Mernoo Bank, in 52 fathoms; Caswell Sound, Fiordland, in 15 and 30 fathoms, R. K. Dell, 23.3.1949; Port Pegasus, Stewart Island, in 5 fathoms, M.V. “Alert,” 23.11.1947; Anchor Island, Dusky Sound, in 5 fathoms; 14 miles W. of Auckland Islands, in 98 fathoms; Chatham Island Exped. St. 4, Chatham Rise, 43° 14′ S., 176° 11′ E. in 200 fathoms; Chatham Island Exped. St. 34, east of Forty Fours, Chatham Islands, in 44° 04′ S., 75° 23.5′ W., in 130 fathoms; Chatham Island Exped. St. 44, N.E. of Kaingaroa, Chatham Islands, 43° 35′ S., 176° 0.3.5′ W. in 120–125 fathoms. Galathea Stations 603, 609, 613 in Milford Sound in depths of 30, 128 and 214 metres respectively; Galathea Station 621, off Milford Sound, 44° 34′ S, 167° 15′ E., in 54 metres. Greatest Diam. of Diam. of Length Diam. Aperture Apex Arc mm mm mm mm mm Topotypes 4.2 0.7 0.6 0.4 0.3 Topotypes 4.6 0.8 0.7 0.4 0.3 Topotypes 3.6 0.7 0.7 0.4 0.2 Topotypes 4.1 0.6 0.5 0.4 0.3 Off Hen and Chickens 4.8 0.8 0.8 0.4 0.3 Off Hen and Chickens 4.4 0.8 0.7 0.4 0.2 Off Hen and Chickens 4.2 0.8 0.6 0.4 0.2 Off Hen and Chickens 4.9 0.9 0.8 0.4 0.2 Off Hen and Chickens 4.2 0.9 0.8 0.4 0.2 Off Hen and Chickens 5.1 0.8 0.7 0.4 0.3

Cadulus colubridens Watsort, 1879. 1879. Cadulus colubridens Watson, Journ. Linn. Soc. London, vol. 14, p. 523. 1886. Cadulus colubridens Watson, Rep. Scientif. Res. “Challenger” Zool. vol. 15, Pt. 42, p. 18, Pl. 3. 1913. Cadulus (Gadila) colubridens Watson; Suter, Man. N.Z. Moll., p. 822, Pl. 32, fig. 6. This species was described from Challenger Station 169 in 700 fathoms but has not been recorded since from New Zealand waters. Boissevain (1906, p. 71) recorded it from two stations in the East Banda Sea, but Ludbrook (1954) has shown that this was evidently a mis-identification. Family Dentaliidae Genus Dentalium Linnaeus 1758 Type species of the genus (subsequent designation, Montfort, 1810), Dentalium elephantinum L. Recent, Amboyna and Philippine Islands. Species belonging to four groups occur in New Zealand waters. These groups correspond fairly well with subgeneric groupings used overseas. The subgeneric groups recognised under Dentalium are urgently in need of revision, but such a revision cannot be attempted with the limited material available in New Zealand. In the meantime they are accepted as subgenera. Finlay (1928, p. 262) has shown that the specimen of Dentalium opacum Sowerby recorded from the Chathams is completely indeterminable, and comments that the “species seems to be a very vague one, and improbably from New Zealand.” It was originally described “from South Sea ships, supposed New Zealand.” Such a designation in 1822 gives little indication of the true provenance of the specimens. From the bare description it might well be identical with Dentalium zelandicum (Sowerby), over which of course it would have priority, but unless the types of opacum Sowerby can be located it seems better to treat it as a nomen dubium. Certainly in the absence of type specimens it can never be recognised. Suter's action (1913, p. 819) in listing D. conicum Hutton as a synonym of opacum is indefensible. Key to Species of Dentalium 1 (1) Shell surface smooth and polished, rather irregularly shaped ecostatum Kirk. 2 (1) Shell ornamented with longitudinal ribs 3 3 (4) Longitudinal ribs 6, often spiralling round shell tiwhana Dell 4 (3) Longitudinal ribs more than 6 5 5 (6) Apex with deep longitudinal slit, ribs numerous, rounded, shells large, up to 88 mm in length zelandicum Sowerby 6 (5) Apex without deep slit, entire or slightly notched, or with projecting pipe 7 7 (10) Riblets, 16–24, apex with slight notch 8 8 (9) Riblets 16, sharp, continuing to aperture of shell, shell tapering rapidly glaucarena Dell 9 (8) Riblets 16–24, very fine, scarcely raised, shell slender, tapering gradually diarrhox Watson 10 (7) Riblets 7–14, apex entire or with projecting pipe 11 11 (12) Apex normally well preserved, tapering to a fine point, up to 38 mm in length nanum Hutton 12 (11) Apex usually truncated with a projecting pipe, up to 45 mm in length suteri Emerson Dentalium tiwhana Dell, 1953. Pl. 39, Figs. 6, 7. Text-figs. 17, 18. 19. 1953. Dentalium tiwhana Dell, Rec. Dom. Mus. vol. 2, p. 48, figs. 17, 22. This species was described from a single specimen obtained in a dredging made by R.R.S. “Discovery II” on the Chatham Rise in 361 metres. The “Galathea” at Station 626, 42° 10′ S., 170° 10′ E. in 610 metres obtained some 22 specimens of this species. Based on this material some additional information can be added to the original description, and some measure can be obtained of the variation present.

Aperture very fragile and usually broken off, but apparently entire, circular in cross section. The youngest portion of the shell is apparently smooth apart from concentric growth rings for some considerable time—up to 6 mm in length. The longitudinal ribbing often commences after a mended break in the shell; in such a case it commences at full strength. It may, however, develop gradually from the smooth posterior end. Primary ribs always six in number. The peculiar irregular spiralling of the longitudinal ribs occurs in most specimens. In some cases the whole shell also becomes twisted to give the appearance of an almost straightened corkscrew. All shells of any size have a number of constrictions along their length and these, together with irregular swellings, result in a most uneven outline. The Chatham Islands Expedition also obtained the species at a number of stations on the Chatham Rise, and it appears to be a characteristic mollusc in depths from 130 to 330 fathoms in this area. Localities: Galathea Station 626, 42° 10′ S, 170° 10′ E., South Tasman Sea in 610 metres. Chatham Island Expedition: Station 4, 43° 14′ S., 176° 11′ E, Chatham Rise in 200 fathoms; Station 5, 43° 32′ S., 178° 38′ E., Chatham Rise in 300 plus fathoms: Station 6, 43° 40′ S., 179° 18′ E., Chatham Rise in 230 fathoms; Station 7, 43° 42′ S., 179° 55′ E., Chatham Rise in 280 fathoms; Station 34, 44° 04′ S., 175° 23.5′ W., east of Forty Fours, Chatham Islands in 130 fathoms; Station 41, 44° 35.5′ S., 176° 04′ W., south-east of Pitt Island, Chatham Islands in 330 fathoms; Station 59, 43° 38′ S., 177° 19′ E., Chatham Rise in 290 fathoms; Portobello “Alert” Station, 54–17, E.N.E. of Taiaroa Head, in 260–350 fathoms, 18.3.1954. Length Apex. Apert. Arc mm mm mm mm C.I.E. St. 41 28.2 1.4 1.6 4.0 C.I.E. St. 59 41.6 0.8 1.5 5.7 C.I.E. St. 59 32.5 0.9 1.6 6.8 C.I.E. St. 59 26.0 0.6 1.9 6.4 Subgenus Fissidentalium Fischer 1885 Type species of the genus (monotypy) Dentalium ergasticum Fischer 1882, Recent. Gulf of Gascony and Atlantic Ocean. Dentalium (Fissidentalium) zelandicum (Sowerby, 1860). Pl. 39, figs. 12, 13. 1860. Dentalium zelandicum Sowerby, Thes. Conch. vol. 3, p. 101, Pl. 223, f. 13. 1873. Dentalium pacificum Hutton, Cat. Mar. Moll., p. 5. 1913. Dentalium (Fissidentalium) zelandicum Sowerby; Suter, Man. N.Z. Moll., p. 819, Pl. 49, fig. 14. No animal of a New Zealand Scaphopod appears to have been studied. The opportunity is taken to give figures showing the gross anatomy of a Cook Strait specimen of Fissidentalium. The captacula were numerous and hair-like, the foot pointed, largely retracted within the mantle in preserved specimens. The buccal mass was crammed with the tests of Foraminifera and numbers of Foraminifera were entangled in the captacula. Hepatic gland, kidney and gonad were all clearly visible from the exterior. The radula (Text-figs. 4, 5, 6) had the usual formula for the group, 1.1.1.1.1. There were 16 rows with five teeth in each row. Central tooth much wider than high, laterals long, cutting edge curved inwards. The number of cusps on the lateral teeth is very variable, and they are often most irregularly arranged. Marginals consisting of elongated flattened plates. Near the apex the riblets are fairly evenly spaced, with interstices concave, wider than the riblets, between 16 and 21 in number, Riblets raised and rounded. They.

gradually become less distinct towards the aperture and their number increases by intercalation. The subsidiary riblets remain less distinct than the primary riblets, but the total number of riblets is variable and they are irregularly arranged. The largest specimen seen is 88 mm in length, the largest specimen of living scaphopod seen from New Zealand. The bathymetric range of living shells as far as known is from 25 to 300 fathoms. So far as it is known the geographical range is from Hauraki Gulf to Fiordland, but it probably extends as far south as the Snares. It also occurs plentifully at the Chatham Islands. Localities: 50 fathoms off Schooner Rock, Bay of Plenty, A. J. Voss,—10.1950; off Hick's Bay, East Cape, in 60 fathoms, A. J. Voss,—.12.1949; off Cape Kidnappers, Hawke Bay, in 15–25 fathoms; numerous localities in Cook Strait from 25 to 100 fathoms; off Kaikoura, in 40 fathoms; F. Abernethy,—.5.1953; Nine Fathom Passage, Dusky Sound, in 9–10 fathoms, W. H. Dawbin, 10.1.1952; Galathea Station 631, off Hawke Bay, 39° 36′ S., 177° 42′ E., in 60 fathoms; B.S. 147, 39° 50.5′ S., 177° 36′ E., Hawke Bay, in 200 fathoms, “Kotuku”, 21.5.1952; B.S. 181, 41° 27′ S., 175° 03′ E., off Palliser Bay, in about 100 fathoms, Victoria University College Zoology Department dredging expedition, 6.2.1955. Chatham Island Expedition: Station 5, 43° 32′ S., 178° 38′ E., Chatham Rise, in 300 plus fathoms; Station 28, 43° 57′ S., 176° 47′ W., Petre Bay, Chatham Islands, in 50 fathoms; Station 29, 43° 55.5′ S., 177° 08′ W., Petre Bay, Chatham Islands, in 94 fathoms; Station 30, 43° 56′ S., 176° 53′ W., Petre Bay, Chatham Islands, in 70 fathoms; Station 34, 44° 04′ S., 175° 23.5′ W., East of Forty Fours, Chatham Islands in 130 fathoms; Station 40, 44° 32′ S., 176° 05′ W., south-east of Pitt Island, Chatham Islands, in 155 fathoms; Station 44, 43° 35′ S., 176° 03.5′ W., north-east of Kaingaroa, Chatham Islands, in 120 fathoms; Station 51, 44° 02′ S., 177° 19′ W., Chatham Rise, in 125 fathoms; Station 60, 43° 34′ S., 175° 30′ E., Chatham Rise, in 205 fathoms. Length Diam. of Aperture Diam. of Apical Aperture Arc mm mm mm mm Bay of Plenty 58.6 7.8 1.4 2.0 Cape Kidnappers 74.8 9.0 2.5 3 1 Hawke Bay, 200 fathoms 65.0 8.2 2.0 1.5 Hawke Bay, 200 fathoms 59.4 6.8 1.6 1.8 Palliser Bay, 100 fathoms 54.2 6.7 1.4 1.7 Palliser Bay, 100 fathoms 55.0 7.0 1.2 2.2 Palliser Bay, 100 fathoms 49.0 6.0 1.1 1 4 C.I.E. Station 60 88 11.5 2.3 1.2 C.I.E. Station 60 82.7 11.2 1.8 2.3 C.I.E. Station 28 58 8.4 1.6 1.9 Subgenus Laevidentalium Cossmann, 1888 1888. Laevidentalium Cossmann, Ann. Soc. Roy. Malac. Belg., vol. 23, p. 7. Type species of the subgenus (o.d.) Dentalium incertum Deshayes, 1825. Eocene of the Paris Basin. Dentalium (Laevidentalium) ecostatum T. W. Kirk, 1880. Text-figs. 10, 13. 1880. Dentalium ecostatum T. W. Kirk, Trans. N.Z. Inst., vol. 12, p. 306. 1913. Dentalium (Laevidentalium) ecostatum T. W. Kirk, Suter, Man. N.Z. Moll., p. 820, pl. 49, fig. 15.

Text-fig. 2.—Fig. 8.—Dorsal and lateral views of animal of Dentalium zelandicum (Sowerby). A, posterior appendage of mantle; B, buccal mass; C, captacula (only a few are shown); F, foot; G, gonad; H, hepatic gland; K, kidney; L, longitudinal retractor muscles; M, mouth; MA, mantle; R, radula. Fig. 9.—Foot of Dentalium zelandicum (Sowerby) (mantle removed). Fig. 10.—Dentalium ecostatum Kirk, type. Fig. 11.—Cadulus delicatulus Suter, type. Fig. 12.—Apex of Cadulus delicatulus Suter. Fig. 13.—Cross section of anterior aperture of type of Dentalium ecostatum Kirk. Fig. 14.—Cross section of anterior aperture of type of Dentalium suteri Emerson. Fig. 15.—Cross section of aperture of Cadulus teliger Finlay. Fig. 16.—Apex of Dentalium nanum Hutton, from off Ahipara. Figs. 17, 18, 19.—Dentalium tiwhana Dell, Galathea Station 626 (all to same scale). Figs. 20, 21, 22.—Apices of Dentalium suteri Emerson, Chatham Id. Exped. St 29 (all to same scale) Fig. 23.—Cadulus teliger Finlay, topotype.

The type specimen of this species is small, obviously malformed, and is not curved in the usual scaphopod fashion. The locality was given as Waikanae Beach, but quite intensive dredging in the western portion of Cook Strait has not as yet brought any other specimens to light in this area. Some doubt might therefore be cast on its provenance, or even its position in the animal kingdom. On the other hand the surface of the shell has a typical smooth scaphopod gloss, and if it is not a scaphopod, the major problem still remains in attempting to determine what it is. One point that must be borne in mind in any consideration of the species is that Kirk's locality data were often inaccurate. However, four small specimens dredged by the “Discovery II” 38° 16′ E., 169° 35′ S., in 536 metres agree very well except as regards size with the type of ecostatum. There is the same glossy surface, irregular growth habit, concentric growth lines and a trace of very faint incipient longitudinal ribbing. From the appearance of these shells the form is almost certainly a scaphopod. The type has never been adequately described, and additional points are therefore given below together with a figure. Shell gradually tapering, hardly curved, cylindrical in cross-section. The shell surface is smooth and polished. There are well marked concentric growth wrinkles, and the shell shows faint incipient ribbing especially near the anterior end. The type shell has evidently sustained an injury about the anterior third, and there is a short period of disturbed growth. Judging by the four fragments from the Discovery II dredging such disturbances are not infrequent. In none of the available specimens are the apical features fully preserved. Dimensions of Type: Length, 15.1 mm; diameter of posterior end, 0.54 mm; diameter of anterior end, 1.95 mm. It is possible that the sparse material available represents the apical fragments of some other species. The chance of it being one of the already named forms is, however, slight. Subgenus Antalis Hermannsen 1846 Type species (s.d. Pilsbry and Sharp, 1897) Dentalium entalis Linn. Recent, North Atlantic Ocean. Dentalium (Antalis) diarrhox Watson, 1879 Pl. 39, fig. 2. 1879. Dentalium diarrhox Watson, Journ. Linn. Soc. Lond.; vol. 14, p. 511. 1886. Dentalium diarrhox Watson, Rep. Scientif. Res. “Challenger,” Zool. Vol. 15, Pt. 42, p. 4, Pl. 1, fig. 5. 1913. Dentalium (Laevidentalium) diarrhox Watson; Suter, Man. N.Z. Moll. p. 820, Pl. 32, fig. 5. This species has not been recorded since it was originally collected by the “Challenger”. Suter (1913, p. 820) referred it to Laevidentalium, but Watson's original description referred to “scarcely impressed longitudinal lines of very equal interval” which faintly marked the whole surface, and the figure shows these as fine slightly raised but definite and regular longitudinal ribs. This is at variance with Laevidentalium which has a smooth, polished shell with transverse growth wrinkles the only form of sculpture. Watson's description refers to a “very narrow, slightly ragged fissure … which lies unsymmetrically on the convex curve.” The figure, however, shows a regular, symmetrical fissure, probably reconstructed by the artist. Some shells obtained from 610 metres by the “Galathea” and one larger specimen from the Chatham Rise agree very well with Watson's description and figures, except that the fissure in well preserved apices is very shallow and rather unsymmetrical. They almost certainly represent diarrhox, although the identity will not be certain until they can be compared with the type. Some details of these specimens are given below. The apex on undamaged specimens is smooth and polished, with a very shallow unsymmetrical notch on the convex curve. Faint, very slightly raised longitudinal ribs are developed on the body of the shell. These are rather widely spaced, 16 to 20 in number on small shells, 23 to 24 on large specimens. The taper is very gradual.

Young shells are comparatively widely curved, but larger specimens that have lost the apical portions are much straighter. For reasons given above this species cannot be retained in Laevidentalium and the best subgeneric location appears to be in Antalis, which contains forms with a prismatic or round tip, with moderate to weak longitudinal sculpture, sometimes with a notch on the convex side of the apex. Localities: Challenger Station 169, north-east of East Cape, in 700 fathoms; Galathea Station 626, 42° 10′ S., 170° 10′ E., Tasman Sea, in 610 metres; Chatham Island Expedition, Station 6, 43° 40′ S., 179° 28′ E., Chatham Rise, in 220 fathoms. Length Diam of Apert. Diam. of Apex Arc mm mm mm mm Galathea St. 626 13.3 1.5 0.5 0.5 Galathea St. 626 12.7 1.3 0.4 1.0 Galathea St. 626 13.9 1.4 0.3 1.1 C.I.E. St. 6 20.5 2.3 0.8 1.3 Dentalium Nanum Complex There are five medium-sized, longitudinally-ribbed Dentalium-like species named from New Zealand, Dentalium nanum Hutton, Dentalium huttoni Kirk, Dentalium marwicki Mestayer, Dentalium suteri Emerson, and Dentalium glaucarena Dell. Dentalium suteri (originally described as Dentalium arenarium Suter 1907 (non Romer 1855), was later classed by Suter in the genus Episiphon Pilsbry and Sharp on the basis of a “projecting pipe” at the apex. The significance of this projecting pipe is somewhat doubtful. Pilsbry and Sharp, in introducing the genus (1897, p. 117) state, “The small accessory tube or pipe at the apex is frequently developed in most, perhaps all, of the species grouped here; although most young and many adult shells lack it.” They based the genus on a number of other characters, including a glossy and smooth surface and the group, as used by them and by Henderson (1920) and Emerson (1952, A and B) seems as distinct as any other subgenus of the genus Dentalium. Dall (1892, p. 436) had already commented on the development of the “tube in tube” structure and had stressed that it was invariably associated with a damaged apex. He also stressed that the condition might well be almost invariably present in the adults of certain species and hence by inference be a suitable taxonomic character. Henderson (1920, p. 77) agrees that the projecting apical pipe may not be a completely diagnostic character, and adds the proviso that it is by no means confined to the particular subgenus. As used by him it is subsidiary to a number of other characters including the lack of longitudinal sculpture. Suter (1913, p. 821) was therefore scarcely justified in including arenarium in Episiphon solely because of the presence of the apical pipe, since the shell is longitudinally grooved. In addition, specimens of the other medium-sized group in New Zealand such as “nanum” occasionally possess a small apical pipe. Dentalium suteri cannot therefore be considered as a member of the subgenus Episiphon and must be considered in conjunction with the other species of the medium-sized group. Dentalium nanum Hutton was described from a fossil specimen from the Castlecliffian and noted as having about 13 longitudinal ribs. The type actually has 12 ribs. Mestayer differentiated D. marwicki (the type of which also comes from the Castlecliffian) as having 9 ribs (variation 8 to 10), and recorded it from a number of recent dredgings, with both species from off Great Barrier Island in 110 fathoms. The situation is by no means as clear-cut as the above would appear to indicate. The mere range of variation as given above (marwicki 8 to 10) nanum 12–13, immediately suggests a possible example of continuous variation, and the examination of additional specimens makes the suggestion much stronger. Much closer analysis

seems necessary therefore before these two species can be satisfactorily differentiated, and this will be attempted later in this paper. As will be shown later, Dentalium suteri also requires comparison with this group. Dentalium huttoni Kirk was based on a specimen from a fish stomach and differentiated mainly by the numerous (18) longitudinal ribs and the lack of secondary longitudinal sculpture. The species has been recorded by Suter (1913, p. 818) from off Great Barrier Island and from off the Auckland Islands. Dentalium glaucarena Dell described from the Chatham Rise in comparatively deep water has more numerous ribs and a rapid taper. Dentalium (Antalis) nanum Hutton, 1873, Pl. 39, figs. 1, 4, 5. 1873. Dentalium nanum Hutton, Cat. Tert. Moll. N.Z., p. 1. 1880. Dentalium Huttoni, T. W. Kirk, Trans. N.Z. Inst. vol. 12, p. 306. 1881. Dentalium nanum Hutton, Suter, Man. N.Z. Moll., p. 818, pl. 49, fig. 17. 1913. Dentalium Huttoni, T. W. Kirk, Suter, Man. N.Z. Moll., p. 818. 1926. Dentalium marwicki Mestayer, Trans. N.Z. Inst., vol. 56, p. 587, Pl. 101, figs. 11, 12. As previously indicated the species grouped around nanum Hutton are difficult of elucidation. Previously all small specimens of Dentalium-like shells have been classed as one of the species in this group. A number of these have proved to be broken apices of Fissidentalium. In addition some records (especially those from off the Snares and off the Auckland Islands) are based on broken fragments. The specific determination of these fragments when no adult specimens are available can only cloak the issue and all such fragments and misidentifications have first to be eliminated. When complete adult shells only are considered two groups emerge amongst this type of Dentalium from the Continental shelf. North of Cook Strait on the east coast and extending as far south of Fiordland on the west coast there is a slender shell, usually with the posterior end well preserved, seldom exceeding 38 mm in length, the longitudinal riblets ranging from 7 to 14 (mode 10) in number. Between Foveaux Strait and Cook Strait and extending to the Chatham Islands there is a proportionately slightly wider shell with the posterior end usually truncated and with a projecting pipe developed. This shell seldom grows more than 24 mm in length, though occasional specimens attain a length of up to 45 mm. The longitudinal riblets range from 8 to 14 in number (mode 10). Juvenile specimens of the southern form cannot be distinguished from specimens of similar size from the north, as the riblet counts are essentially the same and the apical decortication and the formation of the apical pipe have not taken place. These two forms are the only two that are represented in collections by adults. The determination of names for these two forms is comparatively simple; the northern group being consistent with D. nanum Hutton and the southern with D. suteri Emerson. Their claims to specific differentiation are slight but the differences are fairly consistent when well preserved adult populations are considered. They would appear to be closely allied forms but they do not replace one another geographically, and their status must be expressed as specific. This treatment leaves two names as yet unaccounted for—i.e., Dentalium huttoni Kirk and D. marwicki Mestayer. Dentalium huttoni Kirk was described as having unequal longitudinal riblets, about 18 at the anterior end with no secondary longitudinal sculpture. The type series (three shells) were obtained from a fish stomach (probably caught near Wellington). Suter (1913 p. 818) records that two of these shells are no doubt D. nanum, but also records huttoni from off Great Barrier Island, in 110 fathoms, and from north of the Auckland Islands in 85 fathoms. Two of the type series of huttoni are undoubtedly D. nanum, and the remaining specimen, which alone agrees with Kirk's diagnosis, is here selected as lectotype. Examination of this specimen shows that it, too, should be referred to nanum, and the name huttoni Kirk becomes a synonym of this species. The actual specimen is peculiar in that although the broken posterior end shows only 9 strong longitudinal ribs, these have.

increased to 20 at the anterior end by intercalation. These secondary ribs never become fully developed and remain lower than the primary ones. There is no other feature by means of which the type of huttoni may be distinguished from nanum, and this shell is undoubtedly a peculiar individual development of nanum. Suter's specimen from off Great Barrier Island (No. 2967 in the Suter Collection) consists of the apical portion of Fissidentalium zelandicum Sowerby (adults of which have been recorded from the same locality). Suter's records from north of the Auckland Islands in 85 fathoms, consist, as do specimens from the same locality in the Dominion Museum, of shell fragments with evenly developed riblets, nothing like the type of huttoni Kirk, and very possibly fragments of Fissidentalium. The original basis of differentiation of nanum and marwicki has already been outlined, and the suggestion made that these two names have been applied to the two extremes of a group showing continuous variation (i.e., a single species). The situation is somewhat obscured by the fact that both species were based on Castlecliffian fossils but both have been recorded commonly as living shells, and analysis of living population followed by comparison with fossil assemblages should clarify the position. Tabulation of rib counts for individual populations of the northern shells to which the name nanum has been tentatively applied shows that while variation is wide, each population shows a normal distribution curve, with the mode and median the same in most cases. There can be little doubt that each of these populations is homogeneous and that only one form is represented at each locality. For example, in 20 specimens from off the Hen and Chicken in 25–33 fathoms, the number of ribs varies from 9 to 14, the mean and the mode both being 12. Ninety-four specimens from 23 fathoms off Ahipara have from 8–12 longitudinal riblets (mean and mode 10). When all available populations are tabulated it does become apparent, however, that though there is no discontinuity in the variation within any given population, the means do vary from population to population. The population from off Great Barrier Island is the only one showing a bimodal distribution, there being a small peak at 9 and another at 13. A larger sample would undoubtedly eradicate this bimodality. The means of all these populations range from 8 to 13. When all the recent specimens referable to nanum are considered together and the number of riblets are plotted on a frequency table (Text-fig. 24) the distribution takes a bimodal Text-fig. 3.—Fig. 24.—Frequency table for number of riblets in recent specimens of Dentalium nanum Hutton.

form and this might well be an argument for the presence of two distinct forms both with a variable number of ribs, one with a mean number of 10 and the other a mean of 12 riblets. Such a conclusion is, however, discountenanced by the normal distribution of variation within discrete populations, and the examination of a larger number of specimens will undoubtedly show that the number of riblets is distributed normally. The number of specimens examined in each population is given in square brackets immediately after the locality, the mean in parenthesis after the range:– Locality Range of Variation in Riblets Off Big King, in 98 fathoms [5] 10–14 (12) 23 fathoms, off Ahipara [94] 8–12 (10) Tokerau Beach (N. Gardner) [10] 8–10 (9) Off Poor Knights, in 58 fathoms [4] 12–13 (12.5) Off Poor Knights, in 60 fathoms [6] 11–14 (13) Off Hen and Chicken, 25–33 fathoms [20] 9–14 (12) Off Great Barrier Island, in 110 fathoms [10] 8–14 (11) Motutara, Auckland [4] 9–10 (10) Manukau Harbour [6] 9–11 (10) Whatipu, Auckland (N. Gardner) [13] 9–11 (10) 5 miles south of Waikato Heads [3] 9–10 (9) 27 miles off Albatross Point, Mokau [4] 9–11 (10) Flat Point [7] 10–13 (11) 4 miles off Waitara, in 23 fathoms [5] 10–11(10) Cook Strait (various localities) [7] 12–13 (12.5) Galathea St. 609 [30] 10–14 (12) Galathea St. 618 [10] 11–13 (12) Galathea (various, Milford Sound) [13] 11–14 (12) McBeath (1950) in a comparative study of Dentalium nanum and Dentalium marwicki counted the ribs of 405 specimens from rocks of Waitotaran and Nukumaruan age from the Wairarapa. The range of variation was found to be from 7 to 11, mean and mode 9. Similarly 58 specimens from the Castlecliffian ranged from 9 to 13, mean and mode 11. Counts on 269 recent shells showed a range of from 7 to 17, mode 12. On the basis of this increasing mode in populations from Waitotaran age to Recent, McBeath postulated a gradual increase in riblets in these forms of Dentalium, and threw very grave doubt on the validity of marwicki. The present study amplifies the latter conclusion but modifies the figures given for recent shells. These figures, based in part on collections in the Dominion Museum, are inaccurate for the following reason. The recent material, labelled with the nomenclature current at the time, included not only nanum but also specimens which the writer believes should be referred to suteri Emerson and also broken apices of Fissidentalium and material from off the Snares and off the Auckland Islands, which is really indeterminable. This weights the upper range of riblets counts rather considerably. When only the Recent shells that are indubitably referable to nanum are considered the range of variation is considerably less. Collections from additional Nukumaruan localities do seem to have a similar range to that given by McBeath, but Castlecliffian populations are somewhat variable as the following table shows. Castlecliffian shells are thus fairly close in both range of variation and mean rib numbers to Recent shells, but there does appear to be a greater gap between the Waitotaran-Nukumaruan population and Castlecliffian shells. This degree of difference would appear to be subspecific in value, and would probably be best expressed in nomenclature by naming the Waitotaran-Nukumaruan form as a subspecies of nanum. There will be a taxonomic problem involved in that the name marwicki has already been proposed for a Castlecliffian shell which has the characters of the Waitotaran-Nukumaruan form, but which appears to represent an extreme variant of nanum. It is also highly probable that additional Castlecliffian

Fig. 1.—Dentalium nanum Hutton, type. Fig. 2.—Dentalium diarrhox Watson, Chatham Rise. Fig. 3.—Dentallum tiwhana Dell, Chatham Rise. Fig. 4.—Dentalium nanum Hutton, Pickersgill Harbour. Fig. 5.—Dentalium nanum Hutton (Type of Dentalium marwicki Mestayer). Figs. 6, 7.—Dentalium tiwhana Dell, Chatham Rise. Figs. 8, 9.—Dentalium suteri Emerson, Chatham Islands. (Fig. 9 juvenile). Fig. 10.—Dentalium suteri Emerson, Mernoo Bank. Fig. 11.—Dentalium suteri Emerson Type. Figs. 12, 13.—Dentalium zelandicum (Sowerby). Photo: C. Hale.

or Upper Nukumaruan material may well show that the variation is continuous from Waitotaran to Recent, and the separation of subspecies from a series exhibiting continuous variation in geological time is a problem that has not as yet been adequately solved. Consideration of the nomenclature of these fossil forms is best left until the fossil forms can be considered in their entirety. Waitotaran-Nukumaruan Castlepoint [20] 8–11 (9) Petane, Napier [30] 7–11 (9) McBeath's (Waitotaran-Nukumaruan combined) [405] 7–11 (9) Total [435] 7–11 (9) Castlecliffian Castlecliff [12] 8–13 (10) Kai Iwi [13] 10–12 (11) McBeath [58] 9–13 (11) Total [83] 8–13 (11) Recent [107] 7–15 (11) Recent Localities: Off Big King Island, in 98 fathoms; 23 fathoms off Ahipara; off Poor Knights, in 58–69 fathoms; off Hen and Chickens, in 25–42 fathoms; off Cuvier Island, Hauraki Gulf, in 39 fathoms; off Great Barrier Island, in 110 fathoms; Motutara, Auckland (beach shells); Manukau Harbour; 27 miles off Albatross Point, Mokau, in 33 fathoms; 4 miles off Waitara, in 23 fathoms; 5 miles south-west of Waikato Heads, in 18 fathoms: many localities in Cook Strait, from 20 to 100 fathoms. B.S. 144, 39° 31.5′ S., 177° 13′ E., Hawke Bay, in 25 fathoms, “Kotuku”, 20.5.1952. Galathea Stations 603, 609, 610, 611, 615, 616, 617 and 618 in Milford Sound, in depths from 30 to 293 metres. Galathea Station 621, 44° 34′ S; 167° 45′ E., off Milford Sound, in 81 metres. Length Apex Aper Arc mm mm mm mm Manukau Harbour 37.0 1.5 3.0 2.7 Manukau Harbour 37.7 1.5 3.0 2.6 Manukau Harbour 33.3 1.3 2.9 2.8 Manukau Harbour 31.5 1.0 2.5 1.8 Hawke Bay 25.6 0.7 2.3 2.0 Off Ahipara 26.0 0.7 2.3 1.2 Off Ahipara 23.4 0.6 2.1 1.7 Off Ahipara 24.3 0.5 2.2 2.5 Off Ahipara 25.5 0.7 2.2 1.5 Off Ahipara 20.7 0.7 2.0 2.0 Dentalium (Antalis) suteri Emerson 1954. Pl. 39, figs. 8, 9, 10, 11. 1907. Dentalium arenarium Suter, Proc. Mal. Soc. vol. 7, p. 214, pl. 18, f. 11 (non Römer 1855). 1913. Dentalium (Episiphon) arenarium Suter, Manual N.Z. Moll., p. 821, pl. 49, fig. 16. 1954. Dentalium suteri Emerson, Proc. Biol. Soc. Wash., vol. 67, p. 185. The reasons for not considering this species a member of the subgenus Episiphon have already been given, and its apparent close relationship with Dentalium nanum Hutton has been stated. The shell usually grows to about 24 mm in length, and the ribbing is well marked on the posterior end. It gradually becomes obsolete about the anterior quarter. Some specimens do grow to about 45 mm in length, but the larger shells always show progressive loss of sections of the posterior end and hence the diameter of the posterior aperture is always greater in the larger shells. The ribs appear to remain constant in number from the posterior end until they become obsolete, there being no tendency towards intercalation or rib splitting.

There is a strong possibility that this is only a form of nanum in which the formation of a subsidiary tube has become habitual. In all other details apart from the apical characters, populations of suteri may be matched with nanum. The variation in riblet numbers is essentially comparable in both groups, the microscopic surface sculpture, the obsolescence of the riblets with growth, degree of curvature and size may all be matched in series of both forms. In addition, although suteri is predominantly southern in distribution the ranges of the two forms overlap at least in the West Coast Sounds, if not elsewhere, and discrimination of the two forms in region of overlap is impossible if the apices are damaged. On the other hand the presence of an apical pipe is a very obvious feature, and samples of several hundred uniform specimens were obtained from several localities by the Chatham Islands Expedition Under the circumstances, until the significance of the development of an apical pipe is more fully understood, suteri should be given full specific rank. Even very small specimens possess the projecting pipe. One juvenile shell from Chatham Island Expedition Station 28 has an entire posterior end which is sculptured with irregular rugulose concentric wrinkles. The longitudinal ribs commence gradually some distance back. In young shells the interstices between riblets have fine raised striae crossed by fine concentric growth lines. Radula with formula 1.1.1.1.1. (Text-fig. 3). Central tooth wide and fairly flat, laterals with one prominent cusp, marginals elongate, flat. Localities: Port Pegasus, Stewart Island, in 18 fathoms (type); near entrance to Preservation Inlet, W. H. Dawbin, 6.5.1950; 18 miles E.S.E. of Oamaru, in 50 fathoms; Mernoo Bank, 43°. 21′ S., 175° E., in 52 fathoms, N.Z.G.S. “Matai”, 6.11.1936. Chatham Island Expedition:: Station 15, 43° 56′ S., 176° 18.5′ W., Hanson Bay, Chatham Islands, in 30 fathoms; Station 28, 43° 57′ S., 176° 47′ W., Petre Bay, Chatham Islands, in 50 fathoms; Station 29, 43° 55.5′ S., 177° 03′ W., Petre Bay Chatham Islands, in 94 fathoms; Station 30, 43° 56′ S., 176° 33′ W., Petre Bay, Chatham Islands, in 70 fathoms; Station 31, 43° 45.5′ S, 176° 37′ W., Petre Bay, Chatham Islands, in 22 fathoms; Station 38, south of Little Mangere Island, Chatham Islands, in 43 fathoms; Station 40, 44° 32′ S., 176° 05′ W., south-east of Pitt Island, Chatham Islands, in 155 fathoms; Station 44, 43° 35′ S., 176° 3.5′ W., north-east of Kaingaroa, Chatham Islands, in 130 fathoms; Station 60, 43° 34′ S., 175° 30′ E., Chatham Rise, in 205 fathoms. Length** Length without apical pipe. Apex Apert Arc mm mm mm mm C.I.E. 28 25.0 1.6 2.4 1.5 C.I.E. 28 22.5 1.3 2.4 1.1 C.I E. 28 21.7 1.3 2.2 1.3 C.I.E. 28 21.1 1.4 2.1 1.2 C I.E. 28 22.0 1.5 2.3 1.2 Port Pegasus 28.7 1.4 2.7 2.0 Port Pegasus 29.5 1.2 3.0 2.8 Port Pegasus 27.2 1.7 2.5 2.2 Port Pegasus 23.3 1.7 2.8 1.1 Mernoo Bank 31.8 1.4 3.0 3.3 Mernoo Bank 45.4 2.3 3.9 4.7 Dentalium (Antalis) glaucarena Dell, 1953. 1953. Dentalium (Antalis) glaucarena Dell, Rec. Dom. Mus., vol. 2, p. 48, figs. 16, 18, 21. Localities: Chatham Island Expedition: Station 4, 43° 14′ S., 176° 11′ E., Chatham Rise, in 200 fathoms; Station 5, 43° 32′ S., 178° 38′ E., Chatham Rise, in 300 plus fathoms; Station 41, 44° 35.5′ S., 176° 04′ W., south-east of Pitt Island, Chatham Islands, in 330 fathoms.

This species is characterised by the stable number of sharp-edged riblets (15 to 16) which continue through to the anterior end, the rapid taper and slight degree of curvature. Length Diam. of Apert. Diam of Apex Arc Riblets mm mm mm mm Holotype 12.5 1.7 0.8 0.95 16 C I.E. St 41 22 2.4 0.5 1.9 16 C. I. E. St. 41 26.7 2.5 0.6 2.1 16 C.I.E. St. 41 24.3 2.5 0.8 1.3 16 C.I.E. St. 4 21.5 2.7 1.2 1.1 16 C.I.E. St. 4 20.0 2.3 1.1 0.9 15 C.I.E. St. 4 17.0 2.3 1.2 0.7 16 Discussion The bathymetric ranges of the Scaphopods recorded from New Zealand waters are as follows:– Cadulus teliger 5–200 fathoms Cadulus delicatulus 11–330 fathoms Cadulus colubridens 700 fathoms Dentalium zelandicum 25–300 fathoms Dentalium tiwhana 130–330 fathoms Dentalium glaucarena 200–330 fathoms Dentalium nanum 15–160 fathoms Dentalium suteri 18–205 fathoms Dentalium diarrhox 220–700 fathoms Dentalium ecostatum – –300 fathoms These species may be divided into three groups according to their depth tolerances. One group comprising Cadulus delicatulus and Dentalium zelandicum occur from shallow water (5 to 25 fathoms) to as deep as any intensive work has been carried out (300 to 330 fathoms). A second group, Cadulus teliger, Dentalium nanum and D. suteri are confined to the continental shelf, their lower tolerances ranging from 160 to 200 fathoms. The third group, Cadulus colubridens, Dentalium tiwhana, D. glaucarena, D. diarrhox and possibly D. ecostatum belong to the archibenthal zone, their upper tolerances being 130 and 220 fathoms for D. tiwhana and D. glaucarena respectively, the lower tolerances as yet unknown. There is little point in discussing latitudinal ranges within New Zealand, too little being known of the ranges of the deeper ranging forms. None of the species as far as is known range outside the New Zealand area. Except for Dentalium nanum, which appears to be related to the southern Australian D. tasmaniensis Tenison-Woods none of the species appears to have any close relatives in other areas The two common species of Cadulus have peculiar, and very different apical characters and Dentalium tiwhana appears to be a very distinct form. This degree of endemism is of course typical of the bottom dwelling mollusca in general, but it might have been expected that species from deeper water would have a wider distribution. The relatives of the living species must be sought among local Tertiary fossil assemblages. Literature Cited Boissevain, M, 1906. The Scaphopoda of the Siboga Expedition, Siboga-Expeditie, Monograph LIV. Dall, W. H., 1892. Contributions to the Tertiary Fauna of Florida. Trans. Wagner Free Inst. Sci., 3, pt. 2. Dell, R. K., 1953. A Molluscan Fauna from the Chatham Rise, New Zealand. Rec. Dom. Mus, 2: 37–50.

Emerson, W. K., 1952. A. The Scaphopod Mollusks Collected by the First Johnson-Smithsonian Deep-Sea Expedition. Smithson. Miscell. Coll., vol. 117 (b), pp. 1–14. Emerson, W. K., 1952. B. Generic and subgeneric names in the Molluscan class Scaphopoda. Journ. Wash. Acad. Sci., vol. 42, pp. 296–303. Emerson, W. K., 1954. Notes on the Scaphopod Mollusks: Rectifications of Nomenclature. Proc. Biol. Soc. Wash., 67, pp. 183–188. Finlay, H. J., 1928. The Recent Mollusca of the Chatham Islands. Trans. N.Z. Inst., vol. 59, pp. 232–286. Henderson, J. B., 1920. A Monograph of the East American Scaphopod Mollusks. U.S Nat. Mus. Bull. 111. Ludbrook, N. H., 1954. Scaphopoda. John Murray Exped., 1933–34, Scient. Rep., 10 (2). McBeath, D. M., 1950. The Geology of an Area North-east of Martinborough, East Wairarapa. Thesis. Univ. of N.Z., Vict. Univ. Coll. Library. Pilsbry, H. A. and Sharp, B., 1897–8. Man. Conch. (1), 17: 1–348. Suter, H., 1913. Manual of the New Zealand Mollusca, Wellington, N.Z., 1120 pp. R. K. Dell,, B.A., M. Sc., Dip. Ed., Dominion Museum, Private Bag, Wellington.