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ON SOME NEW TASMANIAN MARINE SHELLS.
BY REV. J. E. TENISON-WOODS, F.G.S., etc. Corresponding Member Royal Society, Tasmania; of Victoria; of Linn. Society, N.S.W. Hon. Member Royal Society, N.S.W., etc.
(Read 12th November, 1877.)
The following shells were placed in my hands for description by Mr. W. Legrand, the eminent conchologist of Hobart. They were obtained by the careful researches of Mr. W. F. Petterd, from dredging operations principally in Blackman's Bay. They are (with the exception of a Turbo from King's Island) all small, but of much interest, including a beautiful new species of Crossea. Their general facies is in keeping with the conchology of Tasmania as hitherto known.
TURBO ( ) CUCULLATA. T. turbinato consolida, opaca, sordide albida badia vel atra plus minusve maculata vel ustulata; anfr. 4 1/2, rugosis, vix convexis crebre spiraliter liratis, magis et minoribus alternantibus, tota testa conspicue creberrime oblique squamato-striata; liris majoribus in ult. anfr. fere. 12, distanter granosis vel squamis elevatis cucullatis insignitis, sutura impressa, tenuiter canaliculata apertura orbiculari, integra conspicue marginata, infra. marginem, margaritacea argentea, columella et margine porcellana; basi convexa, lirata. Long. 24, lat. 18 mil. Habit. King's Island, Bass Straits. W. Legrand.
A small turbo with large irregular scorched patches on a dirty white ground. It is spirally closely keeled, with small round alternating keels, on the larger of which there are small tubercles or small raised hooded scales. The whole shell is obliquely closely imbricately striate. The mouth is round without any tubercle, and has an outside margin within which there is a very clearly defined line of silvery nacre which lines the throat. It is very rare, and has more relations with the New Zealand or tropical forms than any Tasmanian congener.
LIOTIA ANNULATA. Testa minuta, discoidea, superne planata et depressa, alba, opaca, anf. 3, circularibus, regulariter subdistanter lamellose annulatis, interstitiis loevibus; apertura integra, orbiculari, antice producta varicifera; umbilico omnino aperto. Maj. diam. 1 1/2 mil. Hab. Blackman's Bay. W. F. Petterd.
Shell minute, discoid, flattened and depressed above, white, opaque; whorls 3, circular, regularly and somewhat distantly ringed with lamellae, interstices smooth, aperture entire, orbicular, anteriorly produced, and bearing a varix round the mouth like one of the rings of the spire, umbilicus entirely open.
I have been long acquainted with this minute shell, but hesitated to describe it until I could find perfect specimens with a true Liotia mouth. I think that even now its generic
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position is doubtful, for the aperture has hardly that thickening which we observe generally in the genus. Its appearance is not unlike some species of Ammonites.
CROSSEA CANCELLATA. n.s. T. minuta, alba, nitente, turbinata; anfr. 3, carinis parvis crebris et striis obliquiis tenuissimis pulcherrime cancellata, apice loevi, pellucido, apertura circulari, antice et postice conspicue canaliculata, labio simplice, basi duobus sulcis unolato altero angusto et in medio eorum costa spirali prope columellam insignita.
A minute white shining turbinated shell of three whorls which are beautifully cancellated by close spiral ribs and distinct oblique striae. The apex is smooth. The aperture is circular and channelled above and below. Behind the inner lip there is a narrow groove forming a false umbilicus, then a rounded spiral rib, and then a broad regularly striate groove on the base. Diam. scarcely 1 1/2 mil. Blackman's Bay. W. F. Petterd.
This minute and very beautiful species adds a fifth to the genus whose synopsis is as follows:-
Shell, varicose. C. miranda. Japan.
---, outer lip, thin. bellulus. Japan.
---, small, whorls shining and punctate. concinna. Port Jackson.
---, somewhat smaller, outer lip fimbriate. labiata. Long Bay, Tasmania.
---, minute, shell cancellate. cancellata. Blackman's Bay, Tasmania.
MARGINELLA. CYPRAEOIDES. T. parva, ovata, cyproeformi, alba, opaca loevi, spira omnino occulta, labro nivea marginato incrassato, postice producto; apertura regulariter arcuata, angusta, columella nivea encausta, ad basim crebre 4 plicata. Long. 6, lat. 4 mil. Blackman's Bay. W. F. Petterd.
Tasmania is already rich in this genus, but this species differs from all in being quite smooth and having the spire quite hidden by the produced and thickened outer lip. From above it appears like a Cyprea. It comes nearest to Marginella volutiformis, but is much smaller and destitute of plaits.
RISSOA ANGELI (mihi) vide Proc. 1876. I find that this shell varies considerably. Sometimes the ribs a very prominent and variciform, and sometimes they are fine and close and scarcely pass to the last whorl, the spiral lirae, which are beautifully delicate, the rounded aperture and umbilicus are constant features. Some authors would place the species in the genus Cyclostrema. It is very minute. Blackman's Bay. W. F. Petterd.
RISSOINA MINUTISSIMA. T. minuta, pyramidata, polita, luteo albida, apice livida, basi pallidisime lutea fasciata; anfr. 5 omnino loevibus, et politis, tenue convexis; labro acuto, producto, labio reflexo; apertura late elliptica antice et postice canaliculata; apice obtuso. Long. 1 1/2; lat. 3/4 mil.
A minute Rissoina destitute of ornament of any kind and
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highly polished. It is yellowish white, and the apical whorls are livid. Blackman's Bay, Tasmania. W. F. Petterd.
RISSOINA UNILIRATA. T. minuta, pyramidata, alba nitente, opaca vel subpellucida, anfr. 5, in spira couspicue carinatis, ultimo anfr. generatim loevi, aliquando unicarinato, semper-autem ad labrum late inflatoque; apice obtuso, nucleo 1 1/2 anfr.; apertura circulari, labro producto, labio reflexo, sutura profunda, unilirata et marginata. Long. 1 1/2; 2 1/2 mil.; lat. 1/2, circiter longitud. Blackman's Bay. W. F. Petterd.
A minute white shell with a conspicuous inflation on the outer lip, and a fine thread which forms a single or double keel on the upper whorls. The last whorl is generally, but not always destitute of these threads, or has only one. The suture has also a thread and is margined. One larger specimen has only one angle in the whorls, which is the result of the one thread-like line proceeding from the last whorl. The shell appears to be variable.
BITTIUM MINIMUM. T. minuta, tumide-pyramidata, badia saturata; nitente; anfr. 7, planatis, regulariter crebre costatis, costis granosis et lineis tribus granorum spiraliter cinctis; costis ex serie granorum confectis; sutura acute impressa; apice decollato, apertura late elliptica, canali brevi obliquo, basi strata tantum, labro simplici, columella incrassata tortuoso. Long. vix. 3 mil.; lat. 1. Blackman's Bay. W. F. Petterd.
This little shell is exactly like Bittium granarium, only that it is a full grown shell and is most minute. The upper whorls seem as if they were margined with a very dark brown line. It is very remarkable that B. granarium varies very much in size, and though I never saw any so small as the present species, still intermediate sizes may yet be found. The ordinary size of that shell is over an inch in length.