SANGUINOLAIUA. CONCHIFERA. 105 



lateral teeth ; epidermis brownish, and under it the shell white, 

 with reddish longitudinal rays, f- inch long, 2 inches broad. In- 

 habits Northern seas. B. Browns Illust. pi. 16, fig. 1, 2. 



P. vespertina, Lam. (Solen, Lin.) Shell oval-oblong, whitish, with 

 reddish violet rays and transverse wrinkles ; umbones yellowish 

 violet, thickest before. Inhabits Mediterranean sea. Chem. vi. 

 pi. 7, fig. 59, 60. 



Gen. 35. SANGUINOLARIA, Lam. 



Shell transverse, subpellucid, slightly gaping at the lateral ex- 

 tremities ; upper margin arched, not parallel to the inferior ; 

 hinge with two approximated teeth in each valve. 



S. rosea, Lam. (Solen sanguinolentus, Lin.) Shell semiorbicular, 

 slightly convex, whitish, with the umbones rose-coloured, and 

 transverse arched striae. 



S. rugosa, Lam. (Venus deflorata, GmeL) Shell ovate-ventricose, 

 white or pale violet colour, transversely wrinkled ; violet colour- 

 ed posteriorly ; anterior depression lanceolate, violet black, pos- 

 terior obsolete. 1^ inch long and 2 broad. Inhabits Indian and 

 European seas Lister, pi. 425, fig. 273. 



FAMILY II. LITHOPHAGI. 



Boring shells, without accessory pieces, and more or less gaping 

 at their anterior side ; ligament of the valves exterior. 



The animals of this family possess the faculty of burrowing in calcareous rocks. 

 How this is accomplished, has been matter of dispute among naturalists, some con- 

 ceiving that the holes are perforated by the mechanical action of the shell alone, 

 while others suppose the existence of a solvent fluid secreted by the animal for this 

 purpose. The anterior extremity of the shell is always placed upwards and towards 

 the opening. 



Gen. 36. VENERUPIS, Lam. 



Shell transverse, inequilateral, with the posterior side very short, 

 and the anterior slighly gaping ; hinge with two teeth in the 

 right valve, three in the left valve, and sometimes three in 

 each ; teeth small, approximated, parallel, and slightly or 

 not at all diverging ; ligament exterior. 



V.perforans, Lam. (Venus, Mont.) Shell subrhomboidal, with 

 transverse striae, forming wrinkles at the anterior end, which is 

 truncated ; hinge with three teeth in each valve, of which one 

 is small, the others long, slender, and curved outwards ; colour 

 white or brownish, with zigzag purple stripes. ^ i ncn l n S an( ^ 

 | broad. Inhabits coasts of England, in limestone. B. Mont. Test. 

 pi. 3, fig. 6. 



V. irus, Lam. Shell rhomboidal, with remote transverse erect mem- 

 branaceous ridges and the margins entire; interstices striated 

 longitudinally ; colour white, with a tinge of brown. Half an inch 

 long, and three-quarters broad. Inhabits European seas, in rocks 

 and stones. B Donov. Brit. Shells, pi. 29. 



