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Volume 71, 1942
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Review of the Tertiary and Recent Neozelanic Pyramidellid Molluscs.
No. 8—The Pyrgulinid Genera And The Genus Evalea.

[Read before the Auckland Institute, June 26, 1940; received by Editor, October 17, 1940; issued separately, June, 1941.]

The writer wishes to acknowledge his indebtedness to Professor J. A. Bartrum for photographing several of the species illustrated in this paper.

1. The Pyrgulinid Genera.

The Pyrgulinid genera are characterised by moderately high conic habit, few whorls, and a single plait on the columella. The outstanding characters of Pyrgulinids, however, are the presence of more or less prominent axial ribs usually evanescing on the base of the shell, together with intercostal spirals of much less strength than the ribs. These two features of ornament are the essential criteria determining separation from true Odostomia.

Pyrgulina itself is limited in the New Zealand fauna to a single species from beds of Hutchinsonian age, after which time the line was apparently not continued in the Neozelanic region. In the same beds another lineage is represented by two species, and for these the new name Linopyrga is employed. This is the most persistent of the Pyrgulinid genera, and is found subsequent to Hutchinsonian times in the Lower Miocene, in Lower, Mid- and Upper Pliocene, and in the Recent fauna. Pukeuria n.gen. and Egila Dall and Bartsch are limited to the Awamoan; Besla Dall and Bartsch appears in the Upper Pliocene and continues on to the present day. Levipyrgulina n.gen. is limited to a single species in each of the Hutchinsonian and Awamoan stages. Elodiamea de Folin is doubtfully represented by a single Eocene species from the greensands at McCullough's Bridge.

Marwick has located his genus Waikura somewhere near Pyrgulina, and for the present one cannot do better than leave its relationship at this. It was provided by its author for two species from Hutchinsonian beds in the Gisborne District; several additional species are now described from Awamoan and Waitotaran rocks.

The occurrence of Chrysallida (Waitotaran at Kaawa Creek) is interesting as it provides the only instance of a highly sculptured Odostomid genus throughout the entire region (the Kermadec Province excepted).

Key to the Pyrgulinid Genera.

Spiral sculpture present as fine, raised, intercostal threads, not incised lines.

Spiral threadlets present and distinct throughout whole length of intercostal spaces of all whorls and on base; axial ribs dying out gradually on base; no peripheral cord present.

Protoconch helicoid. Linopyrga
Protoconch planorboid. Bartrumella
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Spirals very weak in intercostal spaces between sutures and present on last two whorls only, not as distinct threads; strong threads on base; protoconch small, considerably tilted and immersed, no nucleus visible; peripheral cord present, below which ribs suddenly decrease in strength, dying out over base; periphery angulated. Pukeuria
Spiral threads confined to several weak cords around periphery; base not sculptured; axial ribs stopped abruptly at one of the cords, or only obsoletely present below. Besla
Spiral sculpture present as fine, impressed lines.
Impressed spiral lines present in interçostal spaces and on base. Pyrgulina
Impressed spiral lines on base only; body-whorl bi-angulate on periphery, with a flattened or sulcate zone between; axial ribs carried across base. Egila
Spiral sculpture represented by a tumid subsutural border only.
Axial ribs nodulated at summits, dying out very early or just above periphery; whorls flattish; spire gradate; plait very weak, practically absent; aperture rhomboidal. Waikura
Spiral sculpture present as heavy spiral keels.
Axials almost as strong, nodulating keels; spirals strong on base, but axials obsolescent. Chrysallida
Spiral sculpture, if present, limited to fine microscopic striae. Axials ribs dying out gradually at periphery.
Shell well elevated, not squat; whorls not shouldered. Levipyrgulina
Shell not well elevated, stout and inflated; whorls shouldered. Elodiamea
Shell Odostomia-like in all respects save that whorls are plicate; axial ribs weaken in strength near anterior suture. Siogamaia

Genus Linopyrga nov.
Type: Odostomia rugata Hutton.

This new genus has been created for Odostomia rugata Hutton, Odostomia (Pyrgulina) pseudorugata Marshall and Murdoch, and a number of new forms. Murdoch (Trans. N.Z. Inst., vol. 37, p. 227, 1904) referred Hutton's species to Pyrgulina, and this location has apparently been accepted without question. Concerning pseudorugata, Finlay (Trans. N.Z. Inst., vol. 57, p. 406, 1926) has remarked that it is not in direct lineage with rugata Hutton, though closely allied to it. For the present, however, these two forms are here regarded as congeneric.

In typical Pyrgulina the spiral ornament consists of incised lines, but both rugata and pseudorugata have spiral ornamentation of raised threads, not impressed lines, and therefore must be sundered from Pyrgulina. In providing a new location, several names call for consideration. Trabecula Monterosato has raised spiral threads in the interstices, but the strength of these is such as to bring about sculptural reticulation, so that the present shells do not naturally belong here. Further, the shells here referred to Linopyrga have a subsutural swelling, which is not a feature of Trabecula. In Parthenina Bucquoy, Dautzenberg and Dollfus there are only several threads in the interaxial corrugations, and the base is not spirally striated. Besla Dall and Bartsch, of already existing genera, seems to provide the best location, but in this group there are two or three spiral threads low down near the periphery, and the major portion of the whorl lacks intercostal spiral ornament. The tumid subsutural

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border of the species under consideration, and the many distinct, raised spiral threads throughout the entire length of the intercostal spaces and on the base, go to make reference to Besla rather forced, and it is therefore considered that the provision of a new group-name satisfies the position most naturally.

Other salient features of shells of this group are prominent, rounded, oblique axials evanescing gradually, usually not far below the periphery; heterostrophic protoconch of helicoid coiling; and broadly ovate aperture with distinct plait.

Key to Species of Linopyrga.

Shell stoutish, not considerably elevated.

Adult shell about 3 mm. high; 16 axials on penultimate whorl; spiral threads of same strength over whole length of interspaces. rugata
Shell not stout, but considerably elevated. Axials oblique, slightly sinuous.
Adult shell about 4 mm. high; 5 spiral threads on penultimate whorl. pseudorugata
Adult shell considerably less than 4 mm. high.
Axials numerous (9), thin; interspaces sub-equal in width to axials; distinct spiral threads present in interstices. junior
Axials fewer (7), blunter, heavier; interspaces narrower than axials; spiral threads almost obsolete; whorls sulcate. sanguis

Linopyrga rugata (Hutton). (Fig. 1.)

1884.

Odostomia (Parthenia) plicata Hutton, Trans. N.Z. Inst., vol. 17, p. 319, pl. 18, fig. 17.

1886.

Odostomia rugata Hutton, Trans. N.Z. Inst., vol. 18, p. 353.

1893.

Odostomia rugata Hutton, Plioc. Moll. N.Z., Macleay Mem. Vol., p. 58, pl. 7, fig. 51.

1905.

Odostomia (Pyrgulina) rugata Hutton, Murdoch, Trans. N.Z. Inst., vol. 37, p. 227.

1913.

Odostomia (Pyrgulina) rugata Hutton, Suter, Man. N.Z. Moll., p. 344, pl. 17, fig. 8 (Atlas).

1915.

Odostomia (Pyrgulina) rugata Hutton, Suter, N.Z.G.S. Pal. Bull., no. 3, p. 16.

Height, 2·9 mm.; width, 1·35 mm. (holotype).

Localities: Hawera (Waitotaran); Kaawa Creek (Waitotaran); Castlecliff, Wanganui (Castlecliffian), type; Nukumaru (Nukumaruan); Mangapani (Nukumaruan); Eskdale, Petane, Hawke's Bay (Nukumaruan); Maraekakaho, Hawke's Bay (Nukumaruan); Takapuna Beach, Auckland; Hen and Chickens Islands, in 25 fathoms; Awanui Heads, in 16 fathoms (juvenile); Doubtless Bay, in 12 fathoms; off Otago Heads, in from 40 down to 70 fathoms; off Oamaru, in 50 fathoms; Dunedin Harbour; Bounty Islands, in 50 fathoms (a juvenile); Auckland Islands, in 95 fathoms, and at Faith Harbour; Snares Islands, in 50 fathoms; Chatham Islands.

Type and a paratype in Canterbury Museum, Christchurch.

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Linopyrga rugata subsp. parva nov. (Fig. 8.)

Differs from the species in its smaller size and in having considerably finer axial sculpture. In addition, the spiral threads are often sub-obsolete on the posterior part of the interspaces, whereas in rugata they are of even strength throughout. The protoconch has not the bulging lateral nucleus of rugata, and the nucleus is more sunken (about two-thirds emergent in rugata).

Height, 2·3 mm.; width, 1·0 mm. (holotype).

Localities: Takapuna, Auckland, in 4 to 6 fathoms, type; Castlecliff, Wanganui (Castlecliffian).

Type and a number of paratypes in writer's collection.

Linopyrga pseudorugata (Marshall and Murdoch). (Fig. 10.)

1921. Odostomia (Pyrgulina) pseudorugata Marshall and Murdoch, Trans. N.Z. Inst., vol. 53, p. 83, pl. 19, fig. 5.

Marshall's drawing is not a faithful representation of this species. The outline of spire is not straight, but the summit is pupoid; anteriorly the whorls should be contracted to the suture, which is almost channelled; and the plait is given a good deal too much prominence.

Amongst a dozen or so topotypes the writer has one perfectly preserved specimen, which shows the species to be perhaps the most exquisitely ornamented of our Pyramidellids.

Unfortunately the holotype has been lost, so that the large perfect topotype above referred to is here selected as neotype.

Height, 4·5 mm.; width, 1·55 mm, (neotype). Corresponding dimensions of holotype: 3 mm.; 1·0 mm.

Type locality: shell-bed, Target Gully, Oamaru (Awamoan).

Linopyrga junior n.sp. (Fig. 22.)

This is a very close relative of L. pseudorugata. It is, however, constantly a smaller species with sharper and finer axial ribs and a more pronounced subsutural tumid border. In pseudorugata the subsutural tumidity in reality consists of two closely spaced, heavy spirals, and not a single wide, swollen area as in the new species. Further, the penultimate whorl of the former species carries five fine spiral threads, that of the latter seven.

Height, 2·8 mm.; width, 1·0 mm. (holotype).

Locality: Clifden, Southland, band 6C (type); paratypes from bands 6C, 7A, and beds B and C on left side of river = base of band 7 on right side. All are Hutchinsonian horizons.

Type in Auckland Museum (ex Finlay collection).

Linopyrga cf. junior n.sp.

1929. Pyrgulina cf. pseudorugata Marshall and Murdoch, Bartrum and Powell, Trans. N.Z. Inst., vol. 60, p. 429.

This shell agrees well with junior in all respects save that the subsutural border is not so well differentiated.

Locality: Oneroa, Waiheke Island (Hutchinsonian).

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Linopyrga sanguis n.sp. (Fig. 9.)

This is another species of the “pseudorugata” line, and it is closely related to L. junior, also from Clifden. The characters providing separation are fewer, heavier and arcuate axials with very narrow interstices, and smaller shell. The penultimate whorl carries 7 as against 9 axials in L. junior. The fine, regular spiral threads of junior are practically obsolete in the present species, which also has the subsutural tumid band not so pronounced, and in addition two wide, shallow, intercostal spiral sulci anterior to the sutural border.

Height, 2·2 mm.; width, 0·9 mm. (holotype).

Localities: Clifden, Southland, band 7A (Hutchinsonian); Weka Pass, shelly limestone, which is the topmost member of Thomson's E (uppermost Mt. Brown beds). The type is from Clifden.

Type in Auckland Museum (ex writer's collection).

Genus Bartrumella Laws.
1940. Trans. Roy. Soc. N.Z., vol. 69, p. 445.
Type (original designation): Bartrumella kaawaensis Laws.

The genus is of elevated habit, with strong pillar-plait, axial costae, and spiral sculpture (much finer than the axials) developed as fine, raised, intercostal threads. Spirals are present throughout the whole length of the intercostal spaces on all whorls and on base. The posterior spiral (on shoulder) is coarse and nodulates the summits of the axials. The axial ribs evanesce gradually on the base. The protoconch is planorboid. The spirals are not sufficiently strong to cause reticulation of sculpture (as in Trabecula Monterosato), and are just visible under the hand-lens in the type species.

Bartrumella kaawaensis Laws.

1940. Bartrumella kaawaensis Laws, Trans. Roy. Soc. N.Z., vol. 69, p. 446, pl. 61, fig. 45.

Locality: Kaawa Creek (type); shelly streaks in massive argillaceous sandstone, half mile north-west of railway station road, off main Taupo road, Eskdale (N.Z.G.S. loc. 4332); sandstone 110 ch. at 347 from Trig I, Maungaotoro N.W.

Type in writer's collection.

Genus Pukeuria nov.
Type: Pukeuria anaglypta n.sp.

The depressed, tilted embryo with blunt summit points to affinity with the Pyrgulinids. The important post-nuclear characters are the presence of axial ribs extending from summits of whorls to periphery, below which they begin to evanesce, ultimately dying out well down on the base; between sutures the intercostal spaces (on later adult-whorls only) carry weak spiral threads, but below the periphery these become much more elevated and regular, and surmount the prolongations of the axial ribs; the whorls are short between sutures; the aperture is broadly subovate to subquadrate and the columella bears near its insertion a low fold, which strengthens internally; there is a cord on the sub-angled periphery.

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Several genera call for consideration in allotting this shell to its group. The presence of spiral threads on the base precludes Parthenina Bucquoy, Bautzenberg and Dollfus; Besla Dall and Bartsch has a spirally striated base, but it is a different style of shell and the spirals between sutures are confined to several distinct threads at and just above the periphery; Egilina Dall and Bartsch is of somewhat similar build, but lacks spirals between sutures and has very strong basal cords. It is obvious that the characters of the New Zealand fossil do not permit natural reference to any of these groups, and the new name Pukeuria is accordingly provided for it.

Pukeuria anaglypta n.sp. (Fig. 25.)

Shell moderately large, stout, conic, not attenuate, height of spire three times that of aperture, outlines straight. Post-nuclear whorls 6½ in number, lightly and evenly convex; suture distinct though not deeply incised. Protoconch heterostrophic, small, considerably depressed and tilted, so that summit of shell appears blunt; no nucleus visible. Axial ribs (about 20 on penultimate whorl) straight, usually vertical, but sometimes a little oblique, extending from summit of whorls to peripheral cord as stout costae, thereafter on base becoming evanescent towards umbilical region; intercostal spaces excavated, greater in width than ribs; weak spiral threads are present in interstices of later whorls, but on the base they become distinctly elevated, more regular, and surmount the dying axial corrugations. Body-whorl in height less than one-half that of shell, lightly convex to flattish above, periphery angulated (sharply in juvenile shells) and carrying a cord at which the sudden change in strength of axial ribs takes place; base lightly and regularly convex; aperture broadly subovate to subquadrate, the posterior angle wide; columella broad, vertical, lightly arcuate, a small but distinct fold high up; inner lip callused within aperture; basal lip broadly rounded; outer lip straight.

Height, 5·5 mm.; width, 2·6 mm. (holotype).

Localities: Pukeuri, near Oamaru (many specimens), type; Rifle Butts (a single perfect specimen); Awamoa Creek (a juvenile). These are Awamoan horizons near Oamaru. Also Mahoenui beds, Awakino Gorge (Hutchinsonian).

Type in Auckland Museum (ex writer's collection).

Genus Besla Dall and Bartsch.
1904. Proc. Biol. Soc. Wash., vol. 17, p. 10.
Type (original designation) : Chrysallida convexa Carpenter.

The Neozelanic species ascribed to this genus are not confidently located in Besla. They agree in general form and in the possession of peripheral spirals with the genotype as described and figured by Dall and Bartsch, but all lack spirals on the base, which Dall and Bartsch state is a feature of the genus. Of the two species discussed in the monograph of the West American Pyramidellidae convexa has spirals developed over the entire base, and callimorpha has them only over the posterior part of the base. This variation in development of basal spirals amongst American forms justifies location of the Neozelanic species in Besla until such time as descriptions and figures of related genera (e.g., Parthenina) are available.

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Key to Species of Besla.

Height of body-whorl equal to half that of shell.
Shell elevated; umbilicate; axials arcuate, fine, close, numerous. rossiana
Height of body-whorl greater than half that of shell. Axials heavy, not so numerous; shell stumpy, of heavy build; two peripheral cords present.
Axial ribs a little flexuous; the axials ending against posterior peripheral cord; interstices of less width than ribs. subrugata
Axial ribs not flexuous; the axials ending against anterior peripheral cord; interstices as wide as ribs. waitangiensis
Axials not heavy, but fine and numerous; shell not exactly stumpy; of light build; three peripheral cords present.
Axials flexuous; interstices equal in width to ribs; axials ending at anterior peripheral cord. vaga

Besla waitangiensis n.sp. (Fig. 15.)

Shell very small, of stumpy habit, solid; height of body-whorl a little greater than that of shell. Sutures very distinct, whorls strongly convex. Protoconch considerably immersed. Axial ribs (about 12 on last whorl) strong, well elevated, vertical, straight, spaced at about their own width or slightly more. Periphery with two spiral cords, weaker than the axials, which pass through the posterior spiral and end at the anterior one. Base smooth. Aperture ovate. Inner lip thinly callused. Columella arcuate, set vertically, plait represented by a weak swelling well within aperture. Narrow umbilicus present.

Height, 1·5 mm.; width, 0·8 mm.

Locality: Waitangi, Chatham Islands.

Type in writer's collection.

Besla vaga n.sp.(Fig. 7.)

Shell very small, conic, height of spire 1¾ times that of aperture, outlines straight. Post-nuclear whorls 4 in number, lightly convex; suture moderately impressed. Protoconch large, widely convex at summit, considerably obliquely immersed; nucleus not visible. Axial ribs (about 19 on penultimate whorl) thin, sharply elevated, vertical, sinuous, ending abruptly at the anterior one of the peripheral cords, but on some shells they are obsoletely prolonged on to the base; spiral sculpture limited to three intercostal cords around periphery, the posterior cord usually weaker than the other two. Body-whorl in height a little over half that of shell; its outlines convex; aperture subovate, angled behind, moderately widely rounded in front; columella thin, vertical, arcuate, a low fold near insertion, and a little within aperture; basal lip not wide, rather drawn down; outer lip sinuous.

Height, 1·9 mm.; width, 0·9 mm. (holotype).

Localities: Castlecliff, Wanganui (Castlecliffian), type; Hen and Chickens Islands, in 25 fathoms; Big King Island, in 100 fathoms; Poor Knights, in 60 fathoms; off Oamaru, in 50 fathoms; off Otago Heads, in 40–50 fathoms.

Type in Auckland Museum (ex writer's collection).

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Besla rossiana n.sp. (Fig. 4.)

Rossiana differs from the two foregoing forms in the greater elevation of its spire. Its axial ribs, of which there are about 18 on the penultimate whorl, are rather weaker than those of vaga, and are faintly arcuate, not sinuous. A small umbilical chink is present in most specimens. The height of the body-whorl is slightly less than half that of the shell. The most definite means of separation from its associates is the presence of only two spiral cords on the periphery, the posterior one being practically obsolete.

Height, 2·2 mm.; width, 1·0 mm. (holotype).

Localities: Auckland Islands, in 95 fathoms (type); Snares Islands, in 50 fathoms.

Type in Auckland Museum (ex writer's collection).

Besla subrugata (Powell).

1927. Pyrgulina subrugata Powell, Rec. Cant. Mus., vol. 3, pl. 2, p. 118, pl. 22, fig. 6.

The outline of this shell is similar to that of vaga, taken in 50 fathoms off Oamaru. The axial ribs of subrugata, however, are fewer in number, wider and heavier, and the interstices correspondingly narrower. The axials are flexuous, not straight as in vaga. There are but two spiral threads on the periphery, the weak posterior one typical of vaga being absent. The axial ribs end against the upper thread, leaving an uninterrupted spiral furrow between it and the lower thread. This contrasts with its three associates, in each of which the axial ribs extend through the first cord to the lower one, thus fenestrating the ornament of the peripheral part of the shell.

Height, 1·8 mm.; width, 0·9 mm. (holotype).

Locality: off Puysegur Point, south-west Otago, in 170 fathoms.

Type in Canterbury Museum, Christchurch.

Genus Pyrgulina A. Adams.
1864. Journ. Linn. Soc. London (Zool.), p. 4.
Type: Chrysallida casta A. Adams.

The New Zealand representative of this genus is a fossil from Clifden. It is spirally ornamented by regularly spaced impressed lines both in the interstices and on the base, and has strong axial ribs extending from the summit over the base. It therefore falls naturally into Pyrgulina.

Pyrgulina latocorrugata n.sp. (Fig. 3.)

Shell minute, conic, height of spire about 2½ times that of aperture, outlines a little convex. Post-nuclear whorls 3½ in number, strongly convex; suture well incised. Protoconch large, considerably obliquely immersed, so that no nucleus is visible. Axial ribs not numerous (12 on penultimate whorl), narrowly and sharply elevated, thin, straight, vertical, extending well down on to base of shell; interstices very wide and deep, about 3 times width of ribs; spiral sculpture of subequally spaced impressed lines in interspaces on all whorls and on base. Body-whorl half height of shell, shouldered above and convex throughout. Aperture roundly ovate, widely angled behind and broadly rounded in front; columella thin, set

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vertically, arcuate, a very weak plait high up near its insertion; inner lip lightly and narrowly callused; basal lip broad; outer lip straight.

Height, 1·9 mm.; width, 0·9 mm. (holotype).

Locality: Clifden, Southland, bands 4 and 6A (type). Both are Hutchinsonian outcrops.

Type in Auckland Museum (ex writer's collection).

Genus Egila Dall and Bartsch.
1904. Proc. Biol. Soc. Wash., vol. 17, p. 11.
Type: Parthenia lacunata Carpenter.

The New Zealand fossil placed in this group bears a striking resemblance to the figure of Egila poppei* given by Dall and Bartsch in their Monograph. It lacks, however, the strong peripheral sulcus of Egila, but on the body-whorl two angulations are present (the anterior one very weak), and there is a faint depressed zone between these. All the specimens are worn shells, and it is probable that the depth of this more or less sulcate area has been lessened by wearing down of the bordering ridges.

Egila arcuata n.sp. (Fig. 2.)

Shell small, conic, only moderately elevated, height of aperture a little over one-fourth height of shell, outline convex. Post-nuclear whorls 4½ in number, convex, angulated at periphery and overhanging suture; suture very distinct and considerably cut in. Protoconch heterostrophic, very obliquely tilted and immersed so that no part of nucleus is visible. Axial ribs (about 16 on penultimate whorl) weak, vertical, faintly arcuate, becoming obsolete towards lower suture, especially after crossing angulation of whorl; spiral sculpture of impressed lines on base and not between sutures (seen only on good specimens). Body-whorl in height equal to about half that of shell, flattish above, convex over periphery and base; there is a faint secondary angulation close below the periphery, proceeding spirally from posterior end of aperture; aperture subovate, angled behind, broadly rounded in front; columella set vertically, lightly arcuate, its fold very weak and situated high up; inner lip very lightly and narrowly callused; basal lip widely rounded; outer lip straight.

Height, 2·7 mm.; width, 1·0 mm. (holotype).

Localities: Shell-bed, Target Gully, Oamaru, type (Awamoan).

Type in Auckland Museum (ex writer's collection).

Genus Waikura Marwick.
1931. N.Z.G.S. Pal. Bull., no. 13, p. 109.
Type (original designation) : Waikura torques Marwick.

Marwick's diagnosis of this genus reads as follows: “Shell small, subconic; spire telescoped. Protoconch heterostrophic, immersed. Sculpture of tubercles on the shoulder extending axially a short distance, no spirals except subsutural border, surface smooth and polished. Aperture subrhombic; outer lip lightly sinuous, convex below. Columella with a weak fold at the top.”

Marwick has stated that the group is perhaps related to Pyrgulina. It may perhaps be even better compared with a Miralda which has lost all spirals but the infra-sutural crenulated one.

[Footnote] * Monograph, pl. 19, fig. 3.

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Key to Species of Waikura.

Shell stout, solid; axials sharply nodulating summits of whorls, rapidly obsolete below; no peripheral spiral present.
Shell quite stumpy; outline of whorl lightly concave; nodules very sharp; whorls low between sutures. torques
Shell more elevated; outline of whorl straight; nodules blunter; whorls higher between sutures. clivosa
Shell smaller, not so solid; axials not sharply nodulating summits of whorls; peripheral spiral present.
Axials fairly strong, persisting to anterior third; peripheral spiral a distinct, raised thread. hawera
Axials weak, persisting only over posterior half of whorl; peripheral spiral a narrow incised line. finlayi
Shell not stout, appreciably elevated; axials not strongly and sharply nodulated at summits, extending almost to anterior of whorl. circumdata

Waikura torques Marwick. (Fig. 26.)

1931. Waikura torques Marwick, N.Z.G.S. Pal. Bull., no. 13, p. 109, figs. 212, 213

Height, 3·1 mm.; width, 1·4 mm. (holotype).

Localities: Ihungia Series, Gisborne District (Hutchinsonian); N.Z.G.S. locs. 1293, 1295, 1342 (type), 1371.

Type in collection of N.Z. Geological Survey, Wellington.

Waikura clivosa Marwick. (Fig. 16.)

1931. Waikura clivosa Marwick, N.Z.G.S. Pal. Bull., no. 13, p. 109, fig. 211.

Height, 4·2 mm.; width, 1·9 mm.

Locality: Ihungia Series, Gisborne District (Hutchinsonian); N.Z.G.S. loc. 1294.

Type in collection of N.Z. Geological Survey, Wellington.

Waikura cf. clivosa Marwick.

A number of shells from Kaawa Creek, all considerably rubbed, closely resemble clivosa, Good material will probably make it possible to establish identity with the Gisborne species.

Locality: Kaawa Creek (Waitotaran).

Waikura circumdata n.sp. (Fig. 5.)

Shell very small, conic, height of spire 2½ times that of aperture, spire gradate, outlines straight. Post-nuclear whorls 6 in number, flattish, shouldered at summits; suture bordered below by a distinct tumid band. Protoconch low, heterostrophic, the lateral nucleus small, central, about one-half immersed. Axial ribs (16 on penultimate whorl) close, straight, rather oblique, nodulated at summits, dying out just above suture and periphery of last whorl; intercostal spaces narrower than ribs; spiral sculpture, other than the subsutural border, absent. Body-whorl in height a little less than half that of shell, flat above, convex on periphery, lightly convex on base; aperture rhomboidal, angled behind, rounded in front; columella straight, vertical, with a broad, very low swelling above; parieto-columellar junction subangled; inner lip not callused; basal lip narrowly rounded; outer lip lightly convex.

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Height, 3·0 mm.; width, 1·0 mm. (holotype).

Locality: White Rock River, South Canterbury (Awamoan).

Type in Auckland Museum (ex writer's collection).

Shell smaller, more slender and of lighter build than either of the Gisborne species, and the axials not evanescent so early on whorls.

Waikura hawera n.sp. (Fig. 13.)

Shell small, of Odostomid habit; whorls flat, slightly staged; protoconch heterostrophic, helicoid, lateral nucleus partly immersed. Axial ribs strong behind, muricated at summits, dying out at about anterior third; periphery angularly rounded and bearing a thin but distinct spiral thread. Base full, unsculptured. Aperture broadly ovate; columella short, arcuate, set vertically; basal lip broadly rounded; columella-fold distinct, situated near insertion.

Height, 1·7 mm.; width, 0·8 mm. (small individual).

Locality: Hawera (Waitotaran).

Type in writer's collection.

The peripheral thread distinguishes this species from clivosa and torques.

Waikura finlayi n.sp. (Fig. 14.)

Shell very small, spire staged; whorls tabulated at summits, the first post-embryonic one convex, the remainder flat. Height of body-whorl a little greater than half that of shell. Axials weak, developed only over posterior half to third of whorl, their summits faintly muricated and situated along an ill-defined subsutural spiral thread (seen better on a paratype). Parts of an incised spiral line can here and there be picked up on periphery. Protoconch low, helicoid, its lateral nucleus partly immersed. Columella arcuate, set vertically; plait rather heavy, not unduly projecting, situated at insertion.

Height, 2·0 mm.; width, 1·0 mm.

Locality: sandstone from 110ch. at 347° from Trig I, Mangao-toro N.W.

Type in writer's collection.

Genus Chrysallida Carpenter.
1856. Cat. Mazatlan Shells, p. 416.

Type (fide Dall and Bartsch) : Odostomia (Chrysallida) torrita n.n. = Chrysallida communis Carpenter; not Chemnitzia (= Chrysallida) communis C. B. Adams.

In this genus there are strong axial ribs crossed by equally strong spiral keels between sutures. These two elements of sculpture form nodules at their intersection. The axial ribs are very faint on the base, but the spirals remain conspicuous.

There is a single Neozelanic species, confined to the Waitotaran beds at Kaawa Creek.

Chrysallida n.sp.

Shell very small, not unlike the figure of Odostomia (Chrysallida) dux given by Dall and Bartsch (Proc. U.S. Nat. Mus., vol. 30, pl. 17, 1906). Nuclear whorls deeply immersed. Post-nuclear whorls with two heavy spiral cords, nodulated by axials, which, however, are not strong between spirals. Sutures strongly cut in. Axials

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Fig. 1—Linopyrga rugata (Hutton); holotype, X 13. Fig. 2—Egila arcuata n.sp.; holotype, X 13. Fig. 3—Pyrgilina latocorrugata n.sp.; holotype, X 13. Fig. 4—Besla rossiana n.sp.; holotype, X 13. Fig. 5—Waikura circumdata n.sp.; holotype, X 13. Fig. 6—Levipyrgulina marginata n.gen. n.sp.; holotype, X 13. Fig. 7—Besla vaga n.sp.; holotype, X 13. Fig. 8—Linopyrga rugata subsp. parva n.subsp., X 13. Fig. 9—Linopyrga sanguis n.gen. n.sp.; holotype, X 13. Fig. 10—Linopyrga pseudorugata (M. and M.); neotype, X 10. Fig. 11—Siagamaia morioria n.sp.; holotype, X 17. Fig. 12—Evalea sabulosa (Suter); topotype, X 9.2. Fig. 13—Waikura hawera n.sp.; holotype, X 17. Fig. 14—Waikura finlagi n.sp.; holotype, X 17. Fig. 15—Besla waitangiensis n.sp.; holotype, X 17.

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Fig. 16—Waikura clivosa Marwick; holotype, X 13. Fig. 17—Evalea plana n.sp; holotype, X 13. Fig. 18—Elodiamea eocenica n.sp.; holotype, X 13. Fig. 19.—Evalea huttoni Suter; holotype, X 13. Fig. 20—Eralea liricincta Suter; holotype, X 13. Fig. 21—Evalea obsoleta (Murdoch) : holotype, X 13. Fig. 22—Linopyrga junior n.gen. n.sp.; holotype, X 13. Fig. 23—Levipyrgulina sulcata n.gen. n.sp.; holotype, X 13. Fig. 24—Evalea propria n.sp.; holotype, X 13. Fig. 25—Pukeuria anaglypta n.gen. n.sp.; holotype, X 13. Fig. 26—Waikura torques Marwick; holotype, X 13.

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only faintly indicated on base; spirals strong on base, three in number, widely spaced. Aperture with outer lip broken back; columella fairly heavy, arcuate, its fold weak.

Height, 1·6 mm.; width, 0·6 mm.

Locality: Kaawa Creek (Waitotaran).

This is the shell listed by the writer (Trans. Roy. Soc. N.Z., vol. 66, p. 112, 1936) as “Chrysallida n.sp.”, in the list of Kaawa Creek Pyramidellidae. It is interesting in that it is the only Neozelanic record of the genus, and the only instance of a highly sculptured Odostomid group occurring in the region (the Kermadec Province excepted).

Unfortunately the specimen was irreparably smashed after the above description was written, and the name originally allotted the species has had to be deleted.

Genus Levipyrgulina nov.
Type: Levipyrgulina sulcata n.sp.

At present Levipyrgulina accommodates two fossil Pyrgulinids. The generic characters are rather elevated shell, obsolete spirals, and distinct axial ribs evanescing slowly on the periphery. The protoconch consists of planispiral volutions; the plait on the columella, if not strong from without, strengthens within the aperture.

Levipyrgulina marginata n.sp. (Fig. 6.)

Shell small, elongate-conic, outline of spire pupoid. Post-nuclear whorls 5 in number, very flatly convex; suture but little impressed. Protoconch small, of about 1½ planispiral volutions; nucleus lateral, about one-half emergent. Axial ribs (14 on penultimate whorl) thin, rounded, sharply elevated, straight, oblique, dying out a little below periphery; spiral sculpture practically obsolete, only faint traces seen here and there; suture sub-margined by a spiral cord. Body-whorl high, about two-fifths the height of shell, straight above, convex at periphery, which is low; base full, short; aperture angled behind, broadly rounded in front; columella short, vertical, strongly arcuate, its plait weak from outside, but distinctly visible when outer lip is broken back; inner lip descending rapidly, parieto-columellar junction not differentiated; basal lip broad; outer lip straight.

Height, 2·3 mm.; width, 0·7 mm. (holotype).

Locality: shell-bed, Target Gully, Oamaru (Awamoan).

Type in Auckland Museum (ex writer's collection).

Levipyrgulina sulcata n.sp. (Fig. 23.)

Shell small, of rather solid build, spire a little staged, its height 3 to 3½ times that of aperture, outlines convex. Post-nuclear whorls 5 in number, flattish, descending almost vertically; suture not much impressed. Protoconch heterostrophic, well rounded and conspicuous; nucleus lateral, small, partly immersed. Axial ribs (about 15 on penultimate whorl) distinct, straight, vertical, extending from summit of whorls and dying out gradually a little below periphery; intercostal spaces deep, a little narrower than ribs; no spiral sculpture present. Body-whorl flattish above, periphery well rounded, base lightly convex and fairly rapidly drawn in to axis of shell; aperture subrhomboidal to subquadrate, angled behind, broadly

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rounded in front; columella vertical, straight, a little twisted to left below, its plait distinct and situated at insertion; inner lip distinctly callused; basal lip widely rounded; outer lip straight.

Height, 2·65 mm.; width, 1·0 mm. (holotype).

Locality: Clifden, Southland, bands 6A (type), 6C, and bed C on left side of river = base of band 7 on right side (Hutchinsonian).

Type in Auckland Museum (ex writer's collection).

L. marginata is a very much more slender species with pupoid summit and sides parallel below that. The height of whorls between sutures is much greater in relation to their width, the axials oblique and the columella strongly arcuate.

Genus Elodiamea de Folin.
1884. Zool. Record, vol. 22, p. 94; = Elodia de Folin, Les Méléagrinicoles, p. 66, 1867.

Type (fide Dall and Bartsch): Odostomia (Elodiamea) gisna Dall and Bartsch = Elodia elegans de Folin, not Odostomia (Evalea) elegans A. Adams.

Elodiamea covers inflated Pyrgulinids with rounded axial ribs, with or without microscopic striae and with the summits of whorls slightly shouldered.

The reference of the New Zealand species to this genus is not confidently made, as no generic diagnosis (other than the characters given by Dall and Bartsch in their key to genera, p. 13 of their Monograph) and no figure or description of the genotype has been available.

(?) Elodiamea eocenica n.sp. (Fig. 18.)

Shell of moderate size, of stumpy habit, height of spire about 1¾ times that of aperture, outlines convex. Post-nuclear whorls about 4 in number, convex, shouldered at summits; suture impressed. Protoconch missing. Axial ribs (about 18 on penultimate whorl) not strong, rounded, straight, vertical, muricated a little at summits and persisting from summit of whorl on to base, where they gradually die out; intercostal spaces shallow, their width perhaps a little greater than that of the ribs; no spiral ornamentation other than a narrow-swollen subsutural band. Body-whorl in height greater than half that of shell, its outlines convex throughout; aperture subovate, angled behind, rounded in front, where it is twisted slightly towards axis of shell; columella oblique, arcuate, and with no fold; inner lip narrowly and lightly callused; basal lip narrowly rounded; outer lip lightly convex.

Height, 4 2 mm.; width, 2·0 mm.

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

Type in writer's collection.

Genus Siogamaia Nomura.
1936. Saito Ho-on Kai Mus. Res. Bull., no. 10, p. 49.

Type (original designation): Tropaeas (Siogamaia) fortiplicata Nomura. Recent, Japan.

This genus is here used to include forms agreeing with Odostomia in all respects except that they are axially plicate. Nomura's definition of the genus is as follows: “Shell of moderate size, typically many whorled, with elongate conic outline; surface marked by faint

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axial ribs which are developed in earlier whorls only; no marked spiral marking; aperture ovate, with a single prominent fold.”

The Neozelanic shell described below does not conform entirely with the diagnosis of Siogamaia. For instance, it is not elongate-conic; but several of the Japanese species referred to this genus by its author agree with the New Zealand shell in their distinctly Odostomid habit. Neither are the axial ribs of the new species confined to the earlier whorls; but here again certain of the Japanese species (e.g. S. odostomoides) possess plicae on all whorls, including even the body.

Siogamaia morioria n.sp. (Fig. 11.)

Shell small, stout, habit that of Odostomia. Excessively fine microscopic, rather wavy striae seen here and there; an incised spiral line present not far above suture. Axials not strong, low, rounded, confined to posterior two-thirds of whorls, vertical. Colour milk-white. Aperture ovate; columella arcuate, set vertically; plait distinct, situated at insertion of columella. Summit of whorls shouldered and suture slightly channelled. Protoconch appears to be paucispiral, and no projecting lateral nucleus is visible.

Height, 3·0 mm.; width, 1·45 mm.

Locality: Waitangi, Chatham Islands (Recent).

Type in writer's collection.

2. The Odostomid Genus Evalea.

Genus Evalea A. Adams.
1860. Ann. Mag. Nat. Hist., vol. 6, p. 22.
Type: Evalea elegans A. Adams.

In this genus there is an absence of axial ribbing. Axial sculpture in the form of very fine threads fenestrating the incised spiral grooves may, or may not, be present. Spiral sculpture consists of sub-equally spaced incised lines or narrow grooves over the entire adult surface, but weaker on the base. Typically the heterostrophic protoconch is considerably obliquely immersed, so that the nucleus is invisible or nearly so, giving a blunt effect to the top of the shell.

In the Neozelanic region, Evalea does not range back beyond the mid-Pliocene (Nukumaruan). It seems to be a late arrival in New Zealand waters, and the number of species, though yet few, shows a steady increase from Nukumaruan to the present time.

Key to Species of Evalea.

Shell with axial threadlets in spiral grooves.

Incised spirals over whole surface of whorl.
Shell small; spirals quite linear; aperture broad; plait small but distinct; height of body-whorl greater than half that of shell; columella arcuate. obsoleta
Shell larger; spiral groves ont quite linear; aperture narrower; plait low, broad, inconspicuous; height of body-whorl half that of shell; columella less arcuate. sabulosa
Incised spirals absent from central zone of whorl.
Microscopic striae present in addition to incised lines. huttoni
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Shell without axial threadlets in spiral grooves.
Angle of spire not broad; whorls quite convex; suture well cut in.
Incised spirals over whole surface of shell and quite distinct; aperture ovate; height of body-whorl a little over half that of shell. liricinota
Incised spirals obsolete on centre of whorl and not anywhere distinct; aperture broadly ovate; whorls rather more convex; height of body-whorl considerably greater than half that of shell. plana
Angle of spire broader; whorls much less convex; suture not nearly so much incised.
Height of body-whorl greater than half that of shell; body-whorl wide; aperture broadly ovate; incised lines over whole surface of whorl; columella not strongly arcuate, almost straight. propria

Evalea obsoleta (Murdoch). (Fig.21.)

1900. Odostomia (Pyramis) obsoleta Murdoch, Trans. N.Z. Inst., vol. 32, p. 220, pl. 20, fig. 4.

Obsoleta is a near relative of E. sabulosa, and has similar, though not quite so heavy, axial threads in the spiral incisions, which in the latter are not linear and are wider than those of the Wanganui shell. The adult sabulosa is a large shell with a high spire, more cord-like spirals, narrower aperture, not so arcuate a pillar, and 6 spirals, as against 7 in obsoleta, on the penultimate whorl. The protoconch of sabulosa is more prominent, does not give such a blunt effect to the summit of the shell, and overhangs the succeeding whorl.

Height, 2·5 mm.; width, 1·2 mm. (holotype).

Localities: Wanganui (Pliocene), type; Petane, Hawke's Bay (Nukumaruan); Nukumaru.

Type in Wanganui Museum.

Evalea sabulosa (Suter). (Fig. 12.)

1907. Odostomia (Menestho) sabulosa Suter, Trans. N.Z. Inst., vol. 40, p. 367, pl. 29, fig. 15.

1913. Odostomia (Menestho) sabulosa Suter, Man. N.Z. Moll., p. 345, pl. 17, fig. 9 (Atlas).

Finlay (Trans. N.Z. Inst., vol. 57, p. 406, 1926) for reasons there advanced has dismissed the name Menestho from Neozelanic literature. The present writer is also of the opinion that sabulosa has too many features typical of Evalea to permit a natural separation, and agrees with Dr. Finlay's contention that sabulosa should not be severed from such forms as Evalea obsoleta and E. huttoni, which are quite typical Evalea.

Height, 4 0 mm.; width, 1·8 mm. (holotype).

Localities: Bounty Islands, in 50 fathoms (type); Snares Islands, in 50 fathoms; off Otago Heads, in 40–50 fathoms; Dunedin Harbour; Taieri Beach (under stones in muddy sand and on seaweed); Faith Harbour, Auckland Islands.

Type and many paratypes in Wanganui Museum.

For comparison with E. obsoleta see remarks under that species.

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Evalea huttoni Suter. (Fig. 19.)

1885. Odostomia (Pyramis) fasciata Hutton, Trans. N.Z. Inst., vol. 17, p. 320; not of Dunker, 1860.

1893. Odostomia fasciata Hutton, Macleay Mem. Vol., Plioc. Moll., p. 58, pl. 7, fig. 50.

1908. Odostomia (Evalea) huttoni Suter, Trans. N.Z. Inst., vol. 40, p. 368.

1915. Odostomia (Evalea) huttoni Suter, N.Z.G.S. Pal. Bull., no.3, p. 15.

E. huttoni, a Pliocene fossil from Wanganui, approaches E. obsoleta Murdoch. Both hove axial threads present in the incised spiral grooves; but a ready distinction can be drawn in that, whereas obsoleta has impressed lines over the whole surface of whorl, huttoni has a broad band around the centre of the whorl devoid of these. Further, the latter possesses fine microscopic striae on this smooth band as well as on the flat areas between the impressed lines. Obsoleta has no microscopic striae. The impressed spirals of Murdoch's shell are rather wider and the axial threads more conspicuous; otherwise the two species are very closely similar.

Height, 3·0 mm.; width, 1·5 mm. (holotype).

Locality: Castlecliff, Wanganui (Castlecliffian).

Type and an immature paratype in Wanganui Museum.

So far as the writer knows the only other specimen of huttoni is a topotype in the writer's collection.

Evalea liricincta Suter. (Fig. 20.)

1907. Odostomia (Evalea) liricincta Suter, Trans. N.Z. Inst., vol. 40, p. 367, pl. 29, fig. 16.

1913. Odostomia (Evalea) liricincta Suter, Man. N.Z. Moll., p. 343, pl. 17, fig. 7 (Atlas).

Liricincta has no axial threads fenestrating the incised spiral grooves.

Height: 3·0 mm.; width, 1·4 mm. (holotype).

Localities: Port Pegasus, Stewart Island, in 18 fathoms (type); off Otago Heads, in 40–50 fathoms (many shells); Dunedin Harbour; Nukumaru and Mangapani (Nukumaruan).

Type and two paratypes in Wanganui Museum.

Evalea plana n.sp. (Fig. 17.)

Shell of moderate size, conic, height of spire 1¾ times that of aperture, outlines straight. Post-nuclear whorls 4½ in number, evenly convex; suture impressed. Protoconch considerably obliquely immersed; nucleus not visible. All axial sculpture absent; spiral sculpture weak; there are several impressed lines around both upper and lower part of whorls, the centre portion having only traces of obsolete spiral lines; weak impressed lines also present on the base. Body-whorl in height considerably over half that of shell, fairly strongly convex, flatter on base; aperture ovate, angled behind, drawn inwards a little in front; columella set vertically, arcuate, a minute plait at its insertion; parieto-columellar junction not differentiated; inner lip narrowly callused; basal lip convex; outer lip about straight.

Height, 3·1 mm.; width, 1·4 mm. (holotype).

Locality: Snares Islands, in 50 fathoms.

Type in Auckland Museum (ex Finlay collection).

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This species is at first glance very similar to E. liricincta, but closer inspection reveals several points of divergence. In plana the body-whorl is higher between sutures, the whorls more convex and the surface generally smoother. Liricincta lacks the zone around centre of whorl where there is obsolescence of spirals on plana, has more conspicuous plait, less effuse outer lip, and much less arcuate pillar, so that the aperture as a whole is a good deal narrower. Like liricincta it has no axial threads crossing the spiral incisions.

Evalea propria n.sp. (Fig. 24.)

Like liricincta and plana the present species lacks axial threads in the spiral grooves. It is stouter than either and has a much wider and higher body-whorl. The columella is almost straight below, and the basal lip drawn down and inwards to axis even more than that of liricincta. The embryo is more depressed, the whorls less convex and suture less cut in. The incised spiral lines are closer together on the anterior part of the whorl and thus less evenly spaced than those of liricincta, and on the whole the sculpture is weaker than that of Suter's species; in fact, considering the spiral sculpture propria is intermediate between plana and liricincta.

Height, 3·0 mm.; width, 1·9 mm. (holotype).

Localities: Dunedin Harbour (type); Bluff.

Type in Auckland Museum (ex writer's collection).

Evalea impolita (Hutton).

1873. Rissoa impolita Hutton, Cat. Mar. Moll., p. 29.

1878. Rissoa impolita Hutton, J. de Conch., p. 28.

1880. Barleeia impolita (Hutton), Hutton, Man. N.Z. Moll., p. 81.

1904. Odontostoma impolita (Hutton), Hutton, Index Faunae Novae Zealandiae, p. 74.

1905. Odostomia impolita (Hutton), Murdoch, Trans. N.Z. Inst., vol. 37, p. 226, pl. 8, fig. 18.

1913. Odostomia impolita (Hutton), Suter, Man. N.Z. Moll., p. 343, pl. 17, fig. 6 (Atlas).

Finlay (Trans. N.Z. Inst., vol. 57, p. 405; 1926) has shown that this species must be dropped. The type material, he states, consists of several unrecognisable fragments of an Evalea from Stewart Island, where three or four Evaleas occur, so that the only course is to regard Rissoa impolita Hutton as indeterminate.

Appendix.

In a recent paper of this series the name Obex was proposed for Odostomia denselirata Suter and a new species from the Kaawa Creek beds (Trans. Roy. Soc. N.Z., vol. 70, p. 155, 1940). It has since been found that Obex had already been used by Iredale (Rec. Aust. Mus., 14, p. 259, 1925) for a genus of the Cymatiidae. The writer therefore proposes the new name Obexomia with Odostomia denselirata Suter as genotype, and associates with it Obex granum Laws.