Narrative of the Voyage of H.M.S. Rattlesnake Volume Ii Part 45

A very inconspicuous ordinary-looking little sh.e.l.l, its upper surface recalling the aspect of H. alliaria but with more convexity and no l.u.s.tre, and its base that of H. crystallina. It was found, apparently gregarious, under dead leaves in an islet in Trinity Bay.

Balea australis. Tab. 2 fig. 9. a, b.

Testa dextrorsa, rimata, subcylindracea, turrita, decollata, dense capillaceo-costulata, corneo-lutea, maculis obscuris flavidis; sutura impressa; anfractus 11, convexiusculi; apertura pyriformis, columella triplicata, plica inferior maxima, conspicua, elevata, acuta, spiralis; peristoma continuum, solutum. Long. 18--Diam. 4--Apert 4 mill. (Mus.

Brit. & Geol.)

This very remarkable sh.e.l.l, the first of its genus discovered in Australia, differs from all its congeners. It has exactly the aspect of a Clausilia, but the mouth is not furnished with a clausium. It was found under stones at Port Molle.

Pupina grandis. Tab. 2 fig. 10. a, b, c, d.

Testa ovato-subcylindrica, superne laevigata, inferne rugulosa, sordide-rufa; spira obtusa; anfractus 6, secundus tumidus, obliquus, ultimus super aperturam planatus; apertura rotundata; peristoma laete aurantiac.u.m, rimatum, cra.s.sum, dorsaliter ca.n.a.liculatum, infra columellari, profunde sinuatum et in ca.n.a.li contorto excavatum; ca.n.a.lis alter minutus ad partem superiorem et externam aperturae; callus columellaris expansus, appressus. Long. 30, Diam. 15, Apert. 7 mill.

(Mus. Brit. & Geol.).

This, the giant of its genus, is perhaps the most remarkable land-sh.e.l.l discovered during the voyage. It differs from all other Pupinae in having an unpolished surface. It was found in the South-East Island of the Louisiade Archipelago, under dead leaves chiefly about the roots of trees.

Pupina thomsoni. Tab. 3 fig. 2. a, b.

Testa ovata, polita, nitidissima, translucens, hyalina, solidiuscula; spira obtusa; anfractus 5, duo ultimi majores; apertura orbicularis; peristoma alb.u.m, cra.s.sum, solutum, ca.n.a.libus duobus interruptum; ca.n.a.lis superior ad partem superiorem et externam aperturae, inferior major, basalis, marginibus disjunctis et in dorsum anfractus prolongatis. Long.

7 1/2, diam. 4 1/2, apert. 2 mill. (Mus. Brit.)

This remarkable and beautiful little Pupina is most nearly allied to the P. bilinguis of Cape York. From that species (which is larger) it differs, however, very materially, most especially in the position of the inferior or basal ca.n.a.l of the aperture which is here placed like the ca.n.a.l of a whelk, but in P. bilinguis is very small and placed high up, cutting as it were the columella. The curious manner in which the margins of the ca.n.a.ls are prolonged on the back of the body whorl like parallel and somewhat diverging walls is also a singular feature of this species, which is dedicated to Dr. Thomson, surgeon of the Rattlesnake, and an excellent botanist. It was found among dead leaves at the roots of trees in Fitzroy Island.

Helicina stanleyi. Tab. 3 fig. 4. a, b.

Testa lenticularis, superne inferneque convexa, orbicularis, acute carinata, fusco-carnea, spiraliter striata; spira obtusa; anfractus 4 1/2 leviter convexiusculi; basis imperforata, centraliter laevigata, alba; apertura oblique sublunata, angulata; peristoma simplex, tenue. Diam.

maj. 6 1/2, min. 6, alt. 5 mill. (Mus. Brit.)

Found on the leaves and trunks of trees and bushes (especially Scaevola koenigii) in the Duchateau Isles, Louisiade Archipelago. Dedicated to the late Captain Owen Stanley, R.N.

Helicina louisiadensis. Tab. 3 fig. 5. a, b.

Testa depresso-globosa, superne inferneque convexa, orbicularis, obsolete sub-angulata, pallide aurantiaca, sub lente spiraliter striata; spira obtusa; anfractus 4 1/2, vix convexiusculi; basis imperforata, centraliter sub-impressa; apertura lunata, inferne subangulata; peristoma incra.s.satum, aurantiac.u.m, reflexum. Diam. maj. 4 1/2, min. 4, alt. 3 mill. (Mus. Brit.)

On Round Island in Coral Haven, Louisiade Archipelago, under stones. This pretty little Helicina is nearly allied to some Philippine species.

Helicina gouldiana. Tab. 3 fig. 3. a, b.

Testa depresso-globosa, superne sub-conica, orbicularis, obsolete subangulata, flava seu rufa, spiraliter striata; spira prominens; anfractus 5, planati; basis imperforata; apertura sub-lunata, inferne angulata; peristoma incra.s.satum, subreflexum, alb.u.m. Diam. maj. 6, min. 5 1/4, alt. 4 1/2 mill. (Mus. Brit.)

Under the bark of Mimusops kaukii, in the Two Isles, on the North-East coast of Australia. Dedicated to the indefatigable ill.u.s.trator of Australian ornithology.

Ranella pulch.e.l.la. Tab. 3 fig. 6. a, b.

Testa turrita, utroque alata, acute-caudata, alba; anfractus tumidi, spiraliter striati, longitudinaliter noduloso-costati, costis crebris, lateraliter varicosi, varices compressi, aliformes, crenulati, striati, ad margines crenati; apertura ovato-rotunda, inferne longe-caudata; peristoma solutum. Long. 20, diam. 14, apert. 4 mill. (Mus. Brit.)

This beautiful sh.e.l.l was dredged in from 8 to 11 fathoms water, on a bottom of sand and sh.e.l.ls between c.u.mberland Island 1.i, and Point Slade (Lat.i.tude 21 degrees South Longitude 149 degrees 20 minutes East).

The spiral striae that cross its whorls are grouped in pairs; their interstices are raised, and more or less finely crenulated; as they pa.s.s out on the expanded and wing-like varices they diverge, and the lobe-like projections that scallop the margins of the wings are separated from each other by each pair of diverging striae. The fine ribs that cross the whorls are not present on the wings, nor on the back; they are nodulated at their decussation with the raised striae. The wing-like varices of the whorls overlap each other alternately on each side of the sh.e.l.l. The only species to which it has affinity is the R. pulchra.

Scalaria jukesiana. Tab. 3 fig. 7.

Testa lanceolato-turrita, gracilis, alba, laevis, nitida, longitudinaliter costata, costis lamellosis, reflexis, simplicibus, nnmerosis (in ult. anfrac. 20); anfractus 11, tumidi; sutura profunde impressa; varices nulli; apertura orbicularis, margine laevi. Long. 13, Diam. max. 14, apert 3 mill. (Mus. Brit.)

This beautiful little Scalaria is deserving of particular notice on account of the a.n.a.logy and representation which it exhibits with the S.

clathratulus of the seas of the Northern Hemisphere. It is dedicated to the author of the Voyage of the Fly.

New Genus--MACGILLIVRAYIA, Forbes.

Sh.e.l.l spiral, dextral, globular, thin, corneous, transparent (in the only known species smooth or marked by obscure lines of growth) imperforate; spire not produced (with a sinistral nucleus ?). Aperture oblong, entire, angulated below; peristome incomplete, thin, even-edged.

Operculum semicircular, h.o.r.n.y, thin, composed of concentric layers with faint traces of a spiral structure at the centro-lateral nucleus, which is on the columellar side; from it there runs a strait rib or process continued nearly to the outer margin, and indicated externally by a depression or groove.

Animal ample, provided with four very long and rather broad linear rugose (or ciliated ?) tentacula; mantle produced into a long siphon; foot very large, expanded, truncate in front, bearing the operculum near its posterior extremity, but not accompanied by filamentous processes or lobes. A float. (Mus. Brit. and Geol.)

This very remarkable mollusk was taken in the towing net off Cape Byron, on the east coast of Australia, in lat.i.tude 28 degrees 40 minutes South, fifteen miles from the sh.o.r.e. It was floating and was apparently gregarious. Mr. Macgillivray states that it is furnished with a float in the manner of Ianthina. The largest specimens measure rather less than two lines in diameter. The sh.e.l.l is of a yellow horn colour (as is also the operculum) thin and transparent. It bears a striking resemblance to our much more minute Jeffreysia opalina. The four tentacula and the form of the very peculiar operculum also seem to indicate considerable affinity with the genus Jeffreysia of Alder, and an examination of the remains of the tongue extracted from a dried specimen showed an arrangement and form of the lingual denticles very closely resembling that exhibited by Jeffreysia. On the other hand, the very distinct and long siphonal tube delineated in Mr. Macgillivray's drawing, taken when the animal was alive, would seem to refer this genus to some family probably near to Cancellaridae. It is certainly entirely distinct in every respect from any known Gasteropod. It is a form of very great interest to the geologist, for in it we see the nearest representation of certain palaeozoic (especially Lower Silurian) univalves. .h.i.therto referred to Littorina, but which, judging from their a.s.sociates and the indications afforded by the strata in which they are found, were a.s.suredly either inhabitants of deep water or floaters in a great ocean like the Pacific.

I have dedicated this most interesting creature to my friend Mr.

Macgillivray, its discoverer, whose researches have been productive of so much new and valuable contributions to all departments of zoological science.

I have named the species M. pelagica. Tab. 3 fig. 8. a, b, c, d. (Mus.

Brit. and Geol.)

New Genus--CHELETROPIS, Forbes.

Sh.e.l.l spiral, turbinate, dextral, imperforate, spirally ridged or double-keeled and transversely wrinkled; spire prominent, its nucleus sinistral; aperture ovate, ca.n.a.liculated below, its outer margin furnished with two claw-like lobes, the one central and formed by a prolongation of the margin between the keels of the body whorl, the other smaUer and nearer the ca.n.a.l; peristome thickened, reflexed, forming a conspicuous margin.

Operculum none ?

Animal unknown, but certainly floating, and probably pteropodous. This I infer from its habits, and from the a.n.a.logy of the sh.e.l.l with Spirialis.

(Mus. Brit. & Geol.)

The only known species, C. huxleyi (dedicated to Mr. Huxley, a.s.sistant Surgeon of the Rattlesnake, and now eminent for the admirable anatomical researches among marine invertebrata which he conducted during the voyage) is very minute, being not more than the 1/24th of an inch in diameter. It is translucent and of a brownish-white hue. Its aspect is that of a Turbo in miniature. The whorls are tumid, the spire prominent; the body whorl is belted by two prominent keels, one of which is continued on the whorls of the spire: between, above, and below these keels are transverse membranous raised ridges, which in the central division of the body whorl are curved forwards. This curvature corresponds with the projection of the curious incurved claw-like lobe that proceeds from thc central portion of the lower lip. Towards the base of the aperture is a second and similar but smaller lobe, below which is the short but broad and well-marked ca.n.a.l. The entire lip is marginated by the thickened and reflected peristome. I believe this curious floating sh.e.l.l will throw some light on the true nature and habits of several palaeozoic types. It was taken in the towing net, gregarious, in the sea off Cape Howe, the south-east corner of Australia. Tab. 3 fig. 9. a, b.

CONTENTS OF PLATES OF NEW Sh.e.l.lS.

Tab. 2.

Fig. 1. Helix brumeriensis.

Fig. 2. Helix franklandiensis.

Fig. 3. Helix inconspicua.

Fig. 4. Helix iuloides.

Fig. 5. Helix divisa.

Fig. 6. Helix yulei.

Fig. 7. Helix dunkiensis.

Fig. 8. Helix louisiadensis.

Fig. 9. Balea australis.

Fig. 10. Pupina grandis.