78 AX1NUS. 



genus Voluta of Linnaeus, on account of the plaited columella? 

 lip, a character by which that heterogeneous assemblage of shells 

 is distinguished. It forms part of the family of Colimacea, Lam. 

 from which they differ not only in general form, but also in the 

 fact of the animals being partly amphibious, always living (accord- 

 ing to De Blainville) on the sea shore, and being occasionally 

 covered with water for a short time. It contains the genera 

 Pedipes, Auricula, Pyramidella. 



AURIFERA. Bl. Otion, Auct. 



AURIFORM. (FvomAuris, an ear ; forma, shape.) Ex. Haliotis, 

 fig. 338. 



AURISCALPIUM. Megerle. Anatina, Lam. 



AVICULA. Lam. (From Avis, a bird). Fam. Malleacea, Lam. 

 Margaritacea, Bl. — Bescr. Inequivalve, inequilateral, foliaceous, 

 subquadrate, oblique, pearly; hinge rectilinear, lengthened into 

 auricular appendages, with a small indistinct tooth in each valve, 

 an elongated, marginal, ligamentiferous area, and an hiatus in 

 the left valve, for the passage of a byssus ; one circular muscular 

 impression, near the centre of each valve, with a series of smaller 

 ones arranged in a line towards the umbones. — Obs. The Melea- 

 grinse of Lamarck, Margaritiferee, Schum. included in this de- 

 scription, consist of the more rounded species, and do not present 

 the elegant obliquity of form, nor the wing-like auricles from 

 which the genus Avicula receives its name. The Aviculse are 

 pearly within. From A. margaritifera, a young specimen of 

 which is figured in the plates, fig. 164, is obtained oriental 

 pearls. This is an example of Meleagrina. A. Hirundo, fig. 

 163, belongs to the genus Avicula of Lamarck. It is, however, 

 needless to continue the separation. Aviculse are from E. and* 

 W. Indies, Mexico, Coasts of the Pacific, Mediterranean, British 

 Islands, &c. Fossil species occur in the London clay, &c. 



AXINUS. J. Sowerby. — 'Bescr. Equivalve, transverse ; posterior 

 side very short, rounded, with a long ligament, placed in a furrow, 

 extending along the whole edge ; anterior side produced, angu- 

 lated, truncated, with a flattish lunule nearethe beaks. The late 

 Mr. James Sowerby, who described this shell in the Mineral 



