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Volume 56, 1926
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Fossil Mollusca from the Waihao Greensands.

[Read before the Otago Institute, 9th December, 1924; received by Editor, 31st December, 1924; issued separately, 31st March, 1926.]

Plates 76,77.

The present paper deals with fossils collected in the Waihao area. The writer is greatly indebted to Mr. H. J. Finlay and to Dr. J. Marwick for help in connection with nomenclature.

Family Aporrhaidae Philippi.

Perissoptera (Hemichenopus) thomsoni n. sp. (Plate 76, fig. 1.)

This interesting shell is, unfortunately, very incomplete, only the spire being preserved. Dr. Marwick has kindly examined if for the writer; he remarks, “The gasteropod is certainly an Aporrhaid, belonging to the same group as Dicroloma, but without the complete aperture it would be hard to say which genus it most resembles. Hemichenopus Steinmann and Wilckens is a Magellanian Tertiary subgenus of Perissoptera, which may have to be considered. Dr. Marshall say he does not think it is D. zelandica Marshall, the whorls being less convex. Hemichenopus differs from Perissoptera in having only spiral ornament, and in this respect your shell is of intermediate development; but until the aperture is known it would be rash to lay much weight on the generic affinities.”

A description of the spire is as follows:—

Six early whorls and a worn featureless protoconch are preserved. Whorls rapidly increasing in size. Older whorls almost straight, slightly concave above, slightly convex below, ornamented with close even spiral cords about 20 per whorl, interstices of same width with very fine spirals; keel obsolete. Earlier whorls becoming strongly keeled immediately above well-marked suture. Keel ornamented with oblique nodules which become more prominent towards protoconch. Spiral cords crossed by oblique curved growth-lines. Spire-angle 40°. Length of first six whorls 22 mm.; width of sixth whorl, 13 mm.

Locality.—Waihao Downs (Bortonian).

In a paper read before the Australasian Association for the Advancement of Science, 1924, the writer has proposed the new stage name Waimateian for the period represented by the Waihao greensands—i.e., pre-Waiarekan. Further, the Waimateian stage has been subdivided into—(a) the Tahuian substage, with the type locality at McCullough's Bridge, Waihao River; and (b) the Bortonian substage, with the type locality at Borton's, Waitaki River. Both substages are based solely on the contained mollusca.

Family Architectonicidae H. and A. Adams.

Architectonica marwicki n. sp. (Plate 76, fig. 2.)

Shell small, discoidal, spire more elevated than A. ngaparaensis Suter. Sculpture of many fine nodular spirals, giving a highly ornamented surface; a strong spiral above the suture. Body-whorl with a strong median spiral

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rib dividing it into two parts, each of which has three smaller spirals. Periphery strongly keeled, moniliform, nodular ribs crossed by faint radiate growth-lines. Base with nodular spirals, most distinct next to umbilicus. Spire slightly elevated. Protoconch flat, worn. Whorls 5, regularly increasing. Suture inconspicuous. Umbilicus deep with steep sides, showing all the whorls. Aperture broken.

Holotype in author's collection. *

Height, 2 mm.; diameter, 7 mm. (holotype).

Locality.—Waihao greensands, Waihao Downs (Bortonian).

Differs from A. ngaparaensis in the more steeply descending umbilicus, completely nodular sculpture, and the more elevated spire.

Family Eulimidae Adams.

Eulima waihaoensis n. sp. (Plate 76, fig. 3.)

Shell large, smooth, subulate. Whorls 14, body-whorl large in comparison. Sides almost straight, very slightly convex, suture not marked. Protoconch worn. Ornamentation of faint growth-lines only. Aperture narrowly ovate, entire, angulate posteriorly, slightly wider in front; outer lip sharp, inner lip slightly thickened. Varices quite irregular in development.

Holotype in Dominion Museum, collected by S. H. Cox, 1924, and forwarded to the writer for study by Dr. J. A. Thomson. Paratypes in the author's collection.

Length, 18 mm.; width, 5 mm. (holotype).

Locality.—McCullough's Bridge, Waihao (Tahuian).

Family Fasciolariidae Adams.

Fusinus modestus Marshall and Murdoch.

Dr. Marshall (Trans. N.Z. Inst., vol. 54, p. 118, 1923) records this species from McCullough's Bridge. I can find no description of this shell, and it appears to be a nomen nudum inadvertently introduced by that writer.

Fusinus bensoni n. sp. (Plate 76, figs. 4a, 4b.)

Shell large, fusiform, with high turreted spire, axially costate and spirally lirate. Sculpture of heavy radiate pointed nodules, strongest about middle of whorl, obsolete above and below suture; 9 nodules on body-whorl. Spiral sculpture of numerous coarse and fine ribs; the most pronounced rib at convexity of whorls, where it crosses the highest point of nodules. Spirals crossed by faint growth-lines. Spire acute, turreted, less than one-third total length. Protoconch worn. Suture deep, slightly undulating. Whorls 6, regularly descending, carinated a little below middle; body-whorl two-thirds entire length, contracted below. Aperture oval, channelled above, with long straight canal. Outer lip moderately thick, angled above, then convex, contracted below, litrate inside. Columella concave above, convex below. Inner lip narrow, nacreous, as a fine cord anteriorly.

[Footnote] * Owing to the departure of the writer to England, and the consequent dispersal of his collection, the holotypes referred to above as “in author's collection” are now deposited in the Finlay collection. The types of the Naticidae and Volutidae mentioned in Dr. Marwick's papers (Trans. N.Z. Inst., vol. 55, pp. 545–79; vol. 56, pp. 259–303) as being in Mr. R. S. Allan's collection are now deposited in the collection of the New Zealand Geological Survey.

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Holotype and paratypes in author's collection.

Height, 46 mm.; diameter, 15 mm. (holotype). The largest specimen collected is incomplete, but has a diameter of 22 mm.

Locality.—Waihao greensands, Waihao Downs (Bortonian).

This fine species is named in honour of Professor W. N. Benson, B.A., D.Sc., F.G.S., of Otago University, to whom the writer is greatly indebted.

Fusinus delicatulus (Marshall and Murdoch).

1923.

Verconella delicatula M. & M., Trans. N.Z. Inst., vol. 54, p. 123, pl. 14, figs. 3, 4.

This species is evidently closely related to F. solidus, and may prove to be a synonym of it. The axial sculpture seems rather variable.

Locality.—McCullough's Bridge, Waihao (Tahuian).

Verconella formosa n. sp. (Plate 76, fig. 7.)

The paratype of Surcula serotina Suter (N.Z. Geol. Surv. Pal. Bull. 5, pl. 6, fig. 15) is clearly a different shell from the holotype (fig. 12, loc. cit.). S. serotina is described from Waihao Downs, but does not occur at McCullough's Bridge, whereas the paratype is from McCullough's Bridge. Dr. Marwick considers that this new species is identical with Suter's paratype, and places it provisionally under Verconella.

Shell of medium size, fusiform, spirally lirate and axially ribbed. Whorls 5, keeled, ornamentation of numerous spiral cords, interstices finely lirate; crossed by axial ribs most prominent at keel; ribs obsolete on base of body-whorl. Growth-lines show a rounded turrid sinus. Suture deep, bordered below by a band without ribs. Protoconch worn, of 2 ½ whorls; first whorl with numerous small axial ribs. Aperture ovate, anterior canal short (incomplete), open. Outer lip broken; inner lip with thin callus.

Holotype in author's collection.

Length, 20 mm.; diameter, 8 mm. (holotype).

Locality.—McCullough's Bridge (Tahuian).

Verconella spiralis n. sp. (Plate 76, fig. 9.)

Shell moderately small, broadly fusiform; spire turriculated, axially costate and spirally lirate. Sculpture: Protoconch smooth, of 2 ½ whorls; succeeding whorls with prominent axial ribs running from keel to suture below, these tend to become obsolete near base. Ribs rounded, interstices of same width, 19 on body-whorl. Spiral sculpture of many fine dense ribs, finer ribs alternate with coarser ones. Spire turriculate, half length of aperture. Whorls 4, regularly increasing, keel above middle; slightly convex below keel, rapidly descending to suture above. Body-whorl contracted at base. Suture impressed, margined below by a band without axials. Sinus broadly rounded. Aperture slightly oblique, elongate-ovate, canal broken below. Columella vertical, bent to left below. Inner lip narrow, pointed below.

Holotype in author's collection.

Height, 22 mm.; diameter, 10 mm. (holotype).

Locality.—Waihao greensands, McCullough's Bridge, Waihao River (Tahuian).

Verconella uttleyi n. sp. (Plate 76, fig. 6.)

This species agrees in shape, protoconch, and apertural detail with V. spiralis n. sp. The sculpture is much heavier and the axial ribs more

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pronounced, 13 on the body-whorl; 14 main spiral ribs on penultimate whorl; interstices narrower with finer cords.

Holotype in author's collection.

Length, 24 mm.; diameter, 12 mm.

Locality.—“Island sandstone” beds, lower Waihao River (Bortonian).

“Belophos” incertus (Marshall). (Plate 76, fig. 8.)

1919.

Belophos incertus Marshall, Trans. N.Z. Inst., vol. 51, p, 229, pl. 15, fig. 3.

This species is figured from a McCullough's Bridge (Tahuian) specimen to show its close relationship to the three species of “Verconella” here described. Dr. Marshall's original figure was from a specimen which had lost the long canal. Belophos has a deep anterior notch and this species has none, but, as a revision of the family will probably provide a new generic name for the whole group of these forms, Marshall's classification may remain for the present.

Latirus (Peristernia) neozelanicus (Suter). (Plate 76, figs. 5a, 5b.)

1917.

Tudicla neozelanica Suter, N.Z. Geol. Surv. Pal. Bull. 5, p. 17, pl. 11, figs. 17, 18.

Several fine specimens of Tudicla neozelanica Suter were collected by the writer from Waihao Downs and were examined by Dr. Marwick. He considers that the flat spire is like Tudicla, but the aperture is more important and is closer to Peristernia, a subgenus of Latirus, as there is a strong fold at the bottom of the columella. Probably a new generic division is required for this shell.

Family Mitridae Adams.

Conomitra inconspicua (Hutton). (Plate 77, figs. 1a, 1b.)

1885.

Mitra inconspicua Hutton, Trans. N.Z. Inst., vol. 17, p. 326, 1884.

1887.

Mitra inconspicua Hutton, Proc. Linn. Soc. N.S.W. (2), vol. i, p. 212, 1886.

1915.

Mitra inconspicua Hutton: Suter, N.Z. Geol. Surv. Pal. Bull. 3, p. 20, pl. 4, fig. 7.

1924.

Conomitra inconspicua (Hutton): Finlay, Trans. N.Z. Inst., vol. 55, p. 468, pl. 50, figs. 2a, 2b.

Dr. Marwick comments: “Hutton gave as localities Mount Harris and Waihao greensands. Suter says the type is from Mount Harris; but I have seen the two specimens in the Canterbury Museum labelled ‘holotype’ and ‘paratype,’ and they are undoubtedly from the greensands. I have not seen this species from an Awamoan horizon.”

Localities.—McCullough's Bridge (Tahuian) and Waihao Downs (Bortonian).

Conomitra apicicostata (Suter).

1917.

Vexillum apicicostatum Suter, N.Z. Geol. Surv. Pal. Bull. 5, p. 27, pl. 12, fig. 5.

Locality.—McCullough's Bridge, Waihao River (Tahuian).

Vexillum parki n. sp. (Plate 77, fig. 2.)

Shell small, fusiform, turreted. Sculpture of spiral cords, strongest on keel, nearly obsolete near base of body-whorl; spiral cords crossed by axial ribs, well developed on spiral whorls, feebly developed on body-whorl. Spire-whorls with prominent median keel. Sinuous growth-lines ornament

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body-whorl. Spire turreted, slightly shorter than aperture. Protoconch worn. Whorls 6, regularly increasing. Suture deep. Aperture oblique, narrow, truncated posteriorly, produced into a short canal in front. Outer lip broken. Columella oblique, with 4 plaits, the anterior being poorly developed.

Holotype in author's collection.

Length, 15 mm.; diameter, 6 cm. (holotype).

Locality.—McCullough's Bridge, Waihao (Tahuian).

This species is related to V. ligatum Suter from Wharekuri, and to V. rutidolomum Suter from Mount Horrible. It differs from the former in spiral ornament, and from the latter in possessing fewer axial ribs and different shape of whorls.

Family Cancellariidae Adams.

Uxia? marshalli n. sp. (Plate 77, figs. 3a, 3b.)

Shell small, subturriculate, heavily sculptured. Sculpture of heavy axial ribs, 11 on body-whorl. Spiral ornamentation of strong cords separated by much finer threads; the whole surface appears cancellated; 9 main spirals on body-whorl.

Holotype with 4 whorls (broken at apex); paratype with 5 whorls and a worn globular protoconch. Whorls convex. Suture deep. Aperture subtrigonal, with a short open anterior canal. Outer lip varicose, crenate within. Columella with 3 plaits, the anterior being absorbed in the twist of columella.

Holotype and paratype in author's collection.

Length—holotype, 10 mm.; paratype, 12 mm. Diameter—holotype, 5 mm.; paratype, 6 mm.

Dr. Marwick makes the following comments: “Cossmann says that the canal of Uxia has a notch ‘assez profonde,’ but this is not borne out by his figure of the genotype. Uxia has a posterior plait on the parietal wall just as this species has.”

If this determination is found to be valid, this is the first record of Uxia from the Tertiary beds of New Zealand.

Locality.—Waihao greensands, McCullough's Bridge, Waihao River (Tahuian).

Family Olividae d'Orbigny.

Ancilla morgani n. sp. (Plate 77, figs. 4a, 4b.)

Sculpture consists of moderately fine lamellose growth-lines on the smooth part and on the sunken lower band, those of the latter band being inclined

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Description of Plate 76.
Fig. 1.—Perissoptera (Hemichenopus?) thomsoni n. sp. Waihao Downs. × 2.
Fig. 2.—Architectonica marwicki n. sp.: holotype. McCullough's Bridge. × 2.
Fig. 3.—Eulima waihaoensis n. sp.: holotype. McCullough's Bridge. × 2.
Fig. 4a.—Fusinus bensoni n. sp.: holotype. Waihao Downs. × 2.
Fig. 4b.—Fusinus bensoni n. sp.: paratype. Waihao Downs. × 2.
Figs. 5a, 5b.—Latirus (Peristernia) neozelanicus (Suter). Waihao Downs. × 1.5.
Fig. 6.—Verconella uttleyn n. sp.: holotype. “Island sandstone.” × 2.5.
Fig. 7.—Verconella formosa n. sp.: holotype. McCullough's Bridge. × 2.5.
Fig. 8.—Belophos incertus Marshall. McCullough's Bridge. × 2.5.
Fig. 9.—Verconella spiralis n. sp.: holotype. McCullough's Bridge. × 2.5.

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Description of Plate 77.
Figs 1a, 1b.—Conomitra inconspicua (Hutton): topotypes. McCullough's Bridge. × 2.3.
Fig. 2.—Vexillum parki n. sp.: holotype. McCullough's Bridge. × 2.
Fig. 3a.—Uxia? marshalli n. sp.: holotype. McCullough's Bridge. × 3.
Fig. 3b.—Uxia? marshalli n. sp.: paratype. McCullough's Bridge. × 3.
Fig. 4a.—Ancilla morgani n. sp.: holotype. McCullough's Bridge. × 2.5.
Fig. 4b.—Ancilla morgani n. sp.: paratype. McCullough's Bridge. × 2.5.
Fig. 5.—Parasyrinx finlayi n. sp.: holotype. McCullough's Bridge. × 2.3.
Fig. 6.—Conus (Conospira) tahuensis n. sp.: holotype. McCullough's Bridge. × 2.5.
Fig. 7.—Cucullaea waihaoensis n. sp.: holotype. Waihao Downs. × 1.3.
Figs. 8a, 8b.—Limopsis waihaoensis n. sp.: holotype. McCullough's Bridge. × 3.5.
Fig. 9aNuculana belluloides n. sp.: holotype. McCullough's Bridge. × 2.5.
Fig. 9b.—Nuculana belluloides n. sp.: paratype. McCullough's Bridge. × 2.5.

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at a slight angle to those above; these are crossed by exceedingly fine spiral striae; above the smooth band the spire is covered with callus of pearly lustre. Spire equal in height to aperture, acuminate, outlines straight; angle of spire less than 50°. Protoconch small, concealed. Whorls 4; spire-whorls straight; body-whorl convex, restricted, at base. Smooth band slightly less than one-third height of shell. Width of sunken band one-quarter that of smooth band and separated from it by a groove. Aperture half total height, almost rectangular in outline, with a constriction above, deeply notched at base. Outer lip only slightly convex. Columella and inner lip as for A. waikopiroensis.

Holotype and numerous paratypes in author's collection.

Height, 17 mm.; diameter, 7 mm. Aperture—height, 8 mm.; breadth, 3 mm. (holotype.)

Locality.—Waihao greensands, McCullough's Bridge, Waihao River, South Canterbury (Tahuian). Also from the Bortonian beds of Waihao Downs.

This species is nearest to A. waikopiroensis (Suter)—in fact, the shell from Waihao was called A. waikopiroensis by Suter (N.Z. Geol. Surv. Pal. Bull. 5, p. 42). It differs from A. waikopiroensis (Suter) in the following points: The new species is much narrower in proportion to the width; the base is much more constricted; the aperture is distinctly less oval and the outer lip less convex; the chief character of distinction is the relatively very broad depressed band below the smooth area.

Family Turridae H. and A. Adams.

Gemmula bimarginata (Suter).

1917.

Turris bimarginatus Suter, N.Z. Geol. Surv. Pal. Bull. 5, p. 44, pl. 5, fig. 13.

Locality.—McCullough's Bridge (Tahuian).

Gemmula complicata (Suter).

1917.

Turris complicatus Suter, N.Z. Geol. Surv. Pal. Bull. 5, p. 45, pl. 5, fig. 14.

Locality.—McCullough's Bridge (Tahuian).

Gemmula duplex (Suter).

1917.

Turris duplex Suter, N.Z. Geol. Surv. Pal. Bull. 5, p. 45, pl. 5, fig. 15.

Locality.—McCullough's Bridge (Tahuian).

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Parasyrinx finlayi n. sp, (Plate 77, fig. 5.)

Shell small, elongate-fusiform, very strongly keeled. Sculpture: The prominent keel is high on body-whorl but at about middle of succeeding whorls; in both cases its edges are serrated. Body-whorl spirally lirate below keel. Upper three spirals wide apart, middle one strongest. Towards base spirals are closer together and more numerous; they are broken into nodules by radial growth-lines. Except for margined suture, spire-whorls show only very faint spirals. Sinus above keel, and is deep, broad, and rounded. Spire produced, slightly longer than aperture. Protoconch of two smooth and convex whorls. Whorls 5, regularly increasing, concave above and below suture, base contracted below. Suture margined above by a strong cord. Aperture long, ovate, contracted below into a long open canal which is not complete. Outer lip sharp and thin, with well-developed sinus. Columella straight. Inner lip narrow as thin enamel.

Holotype in author's collection; paratype in Dominion Museum, collected by Dr. J. A. Thomson, 1917.

Length, 17 mm.; diameter, 7 mm. (holotype).

Locality.—Waihao greensands, McCullough's Bridge, Waihao (Tahuian).

This is “Ancistrosyrinx n. sp.” of Suter (N.Z. Geol. Surv. Pal. Bull. 8, p. 66, 1921).

Family Conidae Adams.

Conus (Conospira) tahuensis n. sp. (Plate 77, fig. 6.)

Shell fusiform. Sculpture consists of growth-lines showing a rounded sinus above keel. First whorl with traces of axial nodules; later whorls show traces of spiral ribs. Spire elevated, staged. Whorls 5; keel high in body-whorl but below centre on succeeding whorls. Protoconch of 2 whorls, proboscidiform. Suture impressed, margined below. Aperture long, oblique, slit-like, with an open canal.

Holotype in author's collection.

Length, 20 mm.; diameter, 6 mm. (holotype).

Locality.—McCullough's Bridge, Waihao River (Tahuian).

Family Ledidae Adams.

Nuculana solenelloides (Marshall).

1919.

Sarepta solenelloides Marshall, Trans. N.Z. Inst., vol. 51, p. 233, pl. 15, figs. 4, 5, 6.

This Hampden species was recorded from McCullough's Bridge by Dr. Marshall (1923), and was collected by Dr. Thomson in 1917. According to Mr. Finlay, it would be more suitably located in the genus Nuculana.

Nuculana belluloides n. sp. (Plate 77, figs. 9a, 9b.)

Shell small, ovate, equivalve, inequilateral. Beaks approximate, slightly behind anterior third. Anterior end shorter, rounded; posterior margin elongated into a sharp beak, dorsal surface concave; ventral margin gently rounded. Lunule indistinct, escutcheon distinct, lanceolate bounded by a rounded ridge, obliquely longitudinally striate. Sculpture of numerous fine concentric folds. Interior (from paratype) shining, smooth; teeth small, numerous; resilium small, triangular; adductor-scars shallow; pallial line simple; margin simple.

Holotype and paratypes in author's collection.

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Length (holotype, two valves), 10 mm.; breadth, 5 mm.; thickness, 3 mm.

Locality.—McCullough's Bridge (Tahuian).

Family Arcidae Dall.

Cucullaea waihaoensis n. sp. (Plate 77, fig. 7.)

The description is taken from the holotype—a beautifully preserved left valve.

Shell large, thick, somewhat variable in outline, subquadrangular. Anterior margin slightly convex, rounded; posterior dorsal margin almost straight, very slightly rounded. Posterior ventral margin well rounded. Posterior much wider than anterior. Interior porcellaneous, showing faint radial striations inside (i.e., dorsally to) pallial line, which is simple and well defined. Anterior adductor triangular; posterior adductor larger, quadrangular, raised. Margin with many narrow pointed crenulations. Hinge-line straight; hinge-plate solid, lower margin concave. Central taxodont teeth small, numerous; lateral teeth well marked, varying from 4 to 6 in number, 3 or 4 well developed. Lateral teeth grooved or pitted vertically. Area triangular, with 6 incised ligament-pits running obliquely from umbo, which is uncurved and directed anteriorly. Area ornamented with striae parallel to hinge-line. Ornamented with radial ribs crossed by much finer concentric striae, giving a reticulate pattern.

Holotype, from Waihao Downs (Bortonian), in the writer's collection.

Measurements of holotype (left valve): Length, 6.8 cm.; breadth, 5.8 cm.; thickness, 2.5 cm.

Occurs also in the Tahuian beds at McCullough's Bridge.

Relations.—C. waihaoensis differs markedly from the Palaeocene species from Wangaloa and Boulder Hill. It is also distinct from the common Awamoan shell C. attenuata Hutton. It differs from the latter in the smaller size, and especially in the marked difference in number and position of the ligament-grooves.

Family Limopsidae Dall.

Dr. Marshall (1923) records two species—Limopsis aurita (Brocchi) and Limopsis zitteli Ihering.

Mr. Finlay tells me that L. aurita is not a New Zealand shell, and that the shell so called should be referred to as L. zelandica Hutton. Further, both L. zelandica and L. zitteli are known to be restricted to “Miocene” horizons. L. zelandica is characteristic of the Pukeuri beds, while L. zitteli is found typically at Target Gully, Oamaru.

The Waihao specimens, fall into two species, which Mr. Finlay has kindly described for me.

Limopsis campa n. sp.

Young shell irregularly orbicular, adult shell obliquely ovate, elongation occurring ventrally and posteriorly. Ligament area not long, of medium height; pit large, inequilateral; furrow prominent. Beaks very low. Concentric ornament of fine growth-lines. Radial ornament of numerous not quite linear grooves over the whole surface. Posterior area a little frilled, with irregular grooves.

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One of the chief characteristics of this species is the narrowness of the marginal bevelling; the usual broad platform is so limited that it appears like a blunt edge.

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Limopsis campa n. sp. Holotype.

Shell of moderate size; type, 23.5 mm. in height, 25 mm. in length.

Holotype in Mr. Finlay's collection. The writer has numerous meta-types.

Locality.—Waihao greensands, Waihao Downs (Bortonian).

Limopsis waihaoensis n. sp. (Plate 77, figs. 8a, 8b.)

Young shell irregularly orbicular, slightly more quadrate than in L. campa. Adult shell very small for the group, of somewhat similar shape and elongation to L. campa, but rather more oblique, thinner, and more inflated. The tumidity is, in fact, rather pronounced relative to the size of the shell. Ligament area as in L. campa, but the pit is small and either equilateral or compressed. Furrow rather weak. Beaks very low. Concentric ornament of uneven grooves and furrows, forming low ridges at the sides; more pronounced than in L. campa. Radial ornament much finer and closer than in L. campa, almost obsolete over most of the surface but distinct; fine and numerous threads are present on the posterior area, raised into frills on intersecting the concentric furrows. As in L. campa, the marginal bevelling is very narrow—even narrower than in that species.

Height, 6.5 mm.; length, 7.5 mm.

Holotype in Mr. Finlay's collection.

Locality.—Waihao greensands, McCullough's Bridge, Waihao River (Tahuian).