ON TASMANIAN SIPHONARIA, INCLUDING A NEW SPECIES.
By REV. J. E. TENISON-WOODS, F.G.S., &c., Corr. Mem. Roy. Soc., Tas., &c., &c.]
[Read 15th October, 1877.]
Some time since, that is in May, 1876, I read a paper before this Society on some Australian Patellidoe, on which occasion. I referred to two Tasmanian species of Siphonaria, S. denticulata and S. diemanensis, which were the names I supposed them to have received from Messrs. Quoy and Gaimard. (Voyage de l' Astrolabe, Vol. 2, p. 327, and 340.) Since reading that paper I have had an opportunity of seeing type specimens of both these shells, and I find that the one I considered to be identical with S. denticulata, var. Tasmanica mihi., is an undescribed species of a very marked character, to which I now give the name and description found below:-
SIPHONARIA ZONATA. n.sp. S.t. irregulariter ovata, latere siph. distincte subrostrata, tumide conica, alta, vertice mediano, subacuto; costis 40-50, tenuibus, planatis, canali siph. plus minusve interruptis. Coeruleo-albida, lineis vel fasciis olivis varie concentrice zonata, soepe autem atra vel corrosa, intus pulchre nitente intense fulvo pupurea, margine dentata. Impressio muscularis fulvo-albida latere canali irregulariter prolongata.
Shell irregularly oval, distinctly subrostrate on the siphonal side, tumidly conical, high, vertex median, subacute; ribs 40 to 50, thin, flattened, more or less interrupted by the siphonal canal. Color bluish-white, concentrically and variously zoned with olive lines or bands, sometimes the apex is entirely olive, but these lines vary in every shell, often stained black or corroded. The interior is beautifully enamelled, and stained an intense purple brown, with a brownish white spathula which is continued more or less into the siphonal channel. The margin is dentate, rarely dotted with white. The size of the shell varies. Long. 20-25. Lat. 15-19. Alt. 8-12, millimetres.
The animal has been already described in the paper referred to. It generally is found above the tide marks on the hollows of rocks. It appears to be gregarious and is very common on all the South Tasmanian coast. I think I have also seen it on the rocks near Queenscliff, at the entrance to Port Phillip.
In order to point out its affinities I will mention all the species of Siphonaria known as Australian. Siphonaria diemanensis, Quoy and Gaimard, has distinct brown interstices or grooves between the ribs. S. scabra, Reeve, Port Jackson, is a thinner and more depressed shell, though, in my opinion, only a variety of S. diemanensis. Siphonaria denticulata, Quoy and Gaimard, appears to be only another variety, of larger size, somewhat closer ribs, and paler colour. It is totally different in the interior from S. zonata. S. funiculata is another pale variety of S.
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diemanensis, very like S. denticulata, in fact I see no difference, except that it is smaller. S. bifurcata is a thin flat species, of pale internal colour, found in Port Jackson. S. Baconi is a West Australian species, said to occur in South Australia, but the specimens I have seen from South Australia, and those under that name in Port Jackson collections, I should call varieties of S. diemanensis. In Reeve's monograph there are two species named S. funiculata, viz., pl. 2, fig. 6, said to come from Van Diemen's Land, and pl. 7, fig. 35, with an unknown habitat. This has a hooked apex. The specific title of the first species so named may be dropped as only distinguishing a variety of S. diemanensis. I find that Mr. G. F. Angas refers to S. funiculata thus, in the Pro. Zool. Soc. 1867, 232, S f., Reeve, Conch. Icon., pl. 2, fig. 6. "A conical species, ribbed with white, denticulated, and stained in the interior with brown. It varies considerably in colour. Found also in Tasmania, S. atra, Quoy and Gaimard, a Pacific and Japan species is said to occur also in Port Jackson."
In the collection at the Sydney Museum there is a species named S. funiculata, which I should say was only a pale depressed variety of my S. zonata, but it does not in any way correspond with Reeve's description and figure of the first of the two species so named by him. I can only conclude that a mistake has been made in the identification by Australian naturalists, and thus the shell now described, which is an entirely new and distinct species, has been regarded as S. funiculata, Reeve, and so passed over.