Art. XXXV.—Results of Dredging on the Continental Shelf of
[Read before the Auckland Institute, 6th December, 1905.]
Mangilia murrhea (=fluor-spar), n. sp. Figs. 1, 1a.
Shell semitransparent, white. Whorls 4 ½, including a smooth protoconch of one and a quarter whorls. Sculpture: Longitudinal ribs, stronger on the earlier whorls, weaker towards the last, which has about fifteen ribs extending to the suture; these ribs are crossed by faint spirals, the posterior or peripheral being the strongest, two on the second whorl, three above the aperture, a fourth on the body-whorl, beyond which the longitudinal ribs only persist a short distance. The whorls are tabulated above the periphery; a 1 in. objective shows many subsidiary spiral striations between the main spirals. Suture well marked by a narrow overlapping of each whorl by the one following. The base has fifteen spiral striæ. Aperture with a conspicuous sinus in the infrasutural tabulation, but there is no anal fasciole. The type is waterworn. Length, 5 mm.; breadth, 3 mm.
“Allied to M. flexicostata, Suter (H. S.).”
Mangilia infanda (=disreputable), n. sp. Fig. 2.
Shell white, chalky. Whorls 5, rounded, including a smooth protoconch of about one whorl and a half. Sculpture: Longitudinally vertically ribbed, the ribs strong right up to the suture and persisting faintly down the base; body-whorl with about nine ribs. Strong spirals cross the ribs, two on the second
whorl, three above the aperture, a fourth and faint fifth on the body-whorl. The sutures of the early whorls are sharp of those succeeding concavely rounded. The base is spirally striated. The type is worn-the protoconch damaged, and the outer lip broken away for a quarter of a whorl. There are spiral striations between the main spirals, and these are strongest on the somewhat hollow infrasutural tabulation; there is no anal fasciole. Length, 6 mm.; breadth, 3 mm.
“Near M. dictyota, Hutton (H. S.).”
Drillia multiplex, n. sp. fig. 3.
Shell fusitorm, white, chalky. Whorls 5, including a glossy protoconch of one whorl and a quarter; each whorl is tabulated below the suture, and the tabulation ends anteriorly in a prominent spiral thread; then follows a second tabulation, terminating in a row of oval gemmules, about fifteen on the last whorl; just posterior to the gemmules is a fine spiral thread carrying the abruptly curved sharp threads of the anal fasciole; these threads are regularly interspaced, elevated and very distinct on both tabulations; they are covered by the first spiral, but override the second with a sharp downward bend; on the bodywhorl they change their character, becoming mere striations, and more numerous than in the fasciole; in this respect they differ rom Drillia dilecta, Hedley. A second slightly gemmed thread appears on the body-whorl, and two fine spiral lines on the anterior tabulation. On the base are four strong spirals, and on the canal about ten much weaker. The lip is too much broken away to render reconstruction desirable. Length, 5·5 mm.; breadth, 2·5 mm.
I have just seen a recent shell dredged by Mr. C. Cooper off Poor Knights in 70 fathoms; it is pale-pink.
Daphnella aculeata, n. sp. Figs. 4, 4a, 4b.
Shell buff-coloured, lighter towards the apex and canal. Whorls 5, including a reticulated protoconch of one whorl and a quarter. Sculpture: Longitudinally and slightly diagonally ribbed, the ribs crossed by two strong spiral keels, ribs and keels about equal in strength, the intersections forming sharp points. The last whorl has upon the base four additional keels, the space between the two peripheral keels and the four on the base being greater than that between any other two; a fine thread is visible in this wide space, there is also a duplication of the posterior keel; the last whorl has about twelve ribs. The sutures of the early whorls are sharp, those of the latter are concavely round. The columella descends vertically from the body-whorl. The
canal, which is straight, has about eight faint striations. The space between the suture and the first spiral keel contains the anal fasciole; a 1 in. objective reveals faint radial striations between the keels, also the reticulation of the protoconch. Of two shells before me I figure the smaller because it is almost perfect; both shells have five whorls, but the larger has three keels instead of two, the third being introduced near the suture. The sinus of the type is so little damaged that to draw it perfect can scarcely be called reconstruction. Type: Length, 5 mm.; breadth, 3 mm. Larger specimen: Length, 6 mm.; breadth, 3·3 mm.
Newtoniella stiria (=icicle), n. sp. Figs. 5, 5a, 5b.
Shell acicular, pale-yellow, vitreous, with twenty flat whorls, of which three represent the juvenile stage. A 1 in. objective reveals one smooth and two sculptured whorls; the earlier of these two is finely radially ribbed, the latter has in addition spiral striations. The sculpture of the rest of the shell consists of three faintly jewelled spirals to each whorl except the last, which has four. The apex diminishes in diameter with the beginning of the definitive sculpture. Sutures scarcely marked; base smooth; columella spiral, white; canal sharply turned to the left. The outer lip is damaged; a side view therefore shows more of the columella than would otherwise be visible. Length, 9 mm.; breadth, 2 mm.
Triphora infelix, n. sp. Figs. 6, 6a.
Shell of fifteen slightly rounded whorls with a five-whorled juvenile apex. Whorls 6 to 8, have two jewelled spirals, a third being introduced between the other two on the ninth, at which time also a line denoting a fourth spiral appears in the suture, developing into a plain spiral on the last whorl. Sculpture: Oval jewels almost vertically above one another, united longitudinally and spirally by a raised band. Protoconch keeled near the centre of each whorl and finely radiately ribbed. Sutures distinguished by a slightly deeper groove; base with two obscure spirals. Shell rotten, the aperture broken beyond reconstruction; columella wanting. General outline very slightly convex. Length, 6 mm.; breadth, 1·5 mm.
Rissoia pingue (=plump), n. sp. Figs. 7, 7a, 7b.
Shell white, of four and a half rounded but slightly flattened whorls, of which a very glossy protoconch occupies the first one and a half. Sculpture: Fine spiral lines, three on the third and four on the body whorl above the aperture; the spirals are
crossed by close-set longitudinal ribs as strong as the spirals, they die out on a level with the posterior angle of the aperture, and the base has three spirals only. Columella vertically arcuated; aperture diagonal-oval, a little angled where the outer lip joins the columella, behind which is a deep groove. The outer lip is thickened externally, especially where it joins the body-whorl. Length, 2 mm.; breadth, 1·25 mm.
“Near R. gradata, Hutton (H. S.).”
Columbella dæmona, n. sp. Figs. 8, 8a.
Shell dull, pale-cream colour with rufous markings. Whorls 5, slightly rounded, of which the first is glossy without sculpture while the second is finely radiately striated. Sutures well marked; columella vertical, with a slight covering of enamel; lip thin, with twelve faint denticles. Canal with about fifteen obscure strations, the entire shell with fine incremental striæ. Length, 7 mm.; breadth, 2 mm.
Columbella compta (=neat), n. sp. Figs. 9, 9a.
Shell white, with four rather glossy whorls, one of which is the shining protoconch. Sculpture: Close spiral cinguli crossed by fine incremental striæ. There are no spirals visible on the earliest sculptured whorl. Sutures well marked; columella vertical; outer lip thin, devoid of denticles. Length, 3 mm.; breadth, 1 mm.
Explanation Of Plate XXXVIII.
fig. 1Mangiliamurrhea, Webster.
fig. 2. " infanada, Webster.
fig. 3. Drillia multiplex, Webster.
fig. 4.Daphnella aculeata, Webster.
fig. 5.Newtoniella stiria, Webster.
fig. 6.Triphora infelix, Webster.
fig. 7.Rissoia pingue, Webster.
fig. 8.Columbelladæmona, Webster.
fig. 9. " compta, Webster.