42 CONCHOLOGY. 



V. perforans. The perforating Venerirupis. 



Sub-rhombic, transversely striated, wrinkled on the an- 

 terior side ; exterior brown, interior white, sometimes tinged 

 with purple. 



V. irus. The foliated Venerirupis. PI. 7, fig. 2. 

 Species longitudinally striated ; cardinal teeth two, some- 

 times three on the right and three on the left. 



FAMILY VIII. 

 Nymphacea. Ten genera. 



This family is divided into N. Solenaria and N. Tellina- 

 ria, from their resemblance to the Solen and the Tellina. 



N. Solenaria. Three genera. 



1. Sanguinolaria. Four species. 

 This genus may be distinguished from the Solen by never 

 having the transverse oblong shape, or the edge of the valves 

 parallel to the base. 



Sanguinolaria occidens. Sanguinolaria livida. 



S. rosea. S. rugosa. 



S. rosea. The rosy Sanguinolaria. 



Semi-orbicular, smooth, shining and convex ; near the um- 

 bones of a beautiful rose colour, which becomes paler as it 

 descends ; acute transverse striae. 



S. occidens. The setting-sun Sanguinolaria. PI. 7, fig. 4. 



Oval, a little elongated, very compressed, slightly gaping, 

 valves elliptical, equally rounded at the two extremities, with- 

 out mark of posterior keel; summits slightly indicated; hinge 

 formed by one or two contiguous cardinal teeth on each 

 valve ; ligament projecting, convex ; margins not parallel. 



2. Psammobia. Eighteen species. 

 Taken from the Tellina, which it much resembles in form, 

 but from which it differs by not having the irregular plait on 

 the anterior part. 



