430 Mr, A, Adams on the Animal and Affinities of Scaliola. descended, and remained helpless at the bottom of the vessel : the floats were not regenerated or renewed during the period the animals remained alive. Crepitating portions, when sepa-rated, continue buoyant until the vesicles of which they are composed gradually collapse from the escape of the air with which they are distended ; and the floats, when pounded in a mortar, are readily reduced to a mucus. XLVI. — On the Animal and Affinities of Scaliola, a Genus of Mollusca from Japan. By Arthur Adams, F.L.S. &c. In the ' Annals^ for 1860 (vol. vi. p. 120), I gave, under the name of Scaliola, a short description of what I then believed to be a new subgenus of Scala. Since then, however, I have discovered the Mollusk in a living state, and have ascertained, from an examination of the animal, that it is furnished with a rostri-form head, as in Rissoidse, and not with a retractile proboscis as in Scalidse. In all the species I have met with in Japan, its curious habit of agglutinating grains of sand to the surface of the shell is observable. In this peculiarity the genus resembles Onustus and Xenophora ; a species of Helicina likewise exhibits the same remarkable feature. In the original specimens from which I took my first description the foreign particles were worn off. Genus Scaliola, A. Adams. An. capita proboscidiformi. Rostrum elongatum, cylindricum, annulatum. Tentacula filiformia. Oculi prominentes, nigri, ad basin externam tentaculorum positi. Pes brevis, ovatus, postice subacuminatus. Operculum corneum, ovatum, subspirale ; nucleo subterminali. Testa turrita, umbilieata seu rimata; anfractibus agglutinantibus, arenaceis. Apertura plus minusve circularis, peritremate continuo ; margine recto, acuto. The species the animal of which I observed was S. bella, A. Ad. It occurred in considerable numbers at Takano-Sima, a small island near Tatiyama, on the coast of Niphon, in from two to three fathoms, on a bottom of sandy mud. The rostrum is long, large, annulate, bifid at the end, and of a pale yellow colour. The tentacles are small and filiform, with large black eyes at their outer bases. The head is elongated, with a dark median linear mark on the upper surface. The foot is short, ovate, semipellucid, with an opake white blotch on the side near the operculum. 1, Scaliola bella, A. Adams. S. testa pyramidato-turrita, late umbilieata, alba ; anfractibus arenaceis.
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