General Conchology - Or A Description Of Shells, Arranged According To The Linnean System (1835) (Hardcover)

Purchase of this book includes free trial access to www.million-books.com where you can read more than a million books for free. This is an OCR edition with typos. Excerpt from book: Genus 2. L E P A S. GENERIC CHARACTER. Animal Triton. Testa basi affixa multivalvis: valvis inaequalibus erectis. Animal a Triton. Shell of many valves, fixed at the base: valves unequal and erect. GENERAL OBSERVATIONS. Some late authors of repute, both abroad and in this country, struck with the difference of appearance between the conical and compressed shells of this genus, have separated the species, and formed them into distinct 'genera. It has been already stated, that it is not intended in this work to deviate from theLinnaean order; and this determination arises not only from a conviction of its superior utility, but also from a desire to oppose, in some measure, the great inclination which has appeared of late on the Continent to multiply genera; more it is to be feared in some cases to the confusion and prejudice, than the elucidation and advancement, of Natural History. This, however, is no reason why the opinions of other authors should not be regarded; and therefore we shall notice how far they are justified in their proceeding, with respect to the present genus, by considering the following grounds of separation as proposed by Bruguiere. The compressed shells, or barnacles, are generally composed of five valves, not articulated, but merely connected together by a membrane which bounds their circumference. These valves are supported on a flexible pedicle, which the animal can lengthen and contract, or move in any direction at pleasure. The conical, or acorn shells, on the contrary, are generally composed of six valves, which form a kind of pyramidal tube, having all its parts strongly articulated, or joined to each other by delicate sutures. The base is solid and testaceous, by which they firmly fix themselves to other bodies. There are fou...