A treatise on malacology; or, Shells and shell fish . We are not aware that any of these shells have an epi-dermis, and their uniform smoothness leads us to con-clude they are partly covered by the dilated lobes of the 108 SHELLS AND SHELL-FISH. PART I. mantle, as in the Olhnn(P. This, in fact, is the only genuswhich is neither spinecl, muricated, nor spire (6) is conic and somewhat short; the whorls ofthe apex are scarcely papillose ; while the inner marginof the lip is considerably thickened. The plaits on thepillar, as to number, are by no means constant, even inthe same sp
A treatise on malacology; or, Shells and shell fish . We are not aware that any of these shells have an epi-dermis, and their uniform smoothness leads us to con-clude they are partly covered by the dilated lobes of the 108 SHELLS AND SHELL-FISH. PART I. mantle, as in the Olhnn(P. This, in fact, is the only genuswhich is neither spinecl, muricated, nor spire (6) is conic and somewhat short; the whorls ofthe apex are scarcely papillose ; while the inner marginof the lip is considerably thickened. The plaits on thepillar, as to number, are by no means constant, even inthe same species ; in general, there are four, but the lastis always the smallest. Sometimes, however, the pillar,at this part of the aperture, is thickened, and there arefive or even six plaits confused and irregular*, as in S,papillaris (Jig. 12. «). This latter type is remarkable for. its apex, which is suddenly enlarged into a thick nipple-like form (6), similar to Harpula falminata, and verymuch like the published figure of Voluta this, it is clear that we have again arrived, almostunconsciously, among the aberrant forms of the melonvolutes ; ^or fulgetrum connects papillaris to magnifica,which, with the form oi fulgetrum, assumes, as it were,that particularly large spire which is the chief characterof the genus Foluta. Scaphella papillaris, on the otherhand, is closely connected to our S. fusiformis, whichthus unites it also to S. nndulata. (99) Here we close our remarks on the affinities ofthese magnificent shells ; but, before we enter upon theconsequences of this distribution, we shall endeavour tomeet some objections which may possibly be raised * This deviation is not uncommon in Scaphella vndulafa : four is theusual number of the plaits ; but sometimes, as Lamarck observes, there aretwo smaller and supernumerary ones. (Lam. ^).)
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Keywords: ., bookcentury1800, bookdecade1840, booksubjectmollusks, bookyear184
