ELIZIA. 393 



Sub-gen. psammot^a, Lamarck (Capsella, Desk., not Gray). 



Shell with the hinder slope somewhat angulated, not beaked ; 

 valves smooth, covered with an epidermis. 



Chinensis, Desk. rosacea, Desk. 



crassula, Desk. rufa, Desh. 



difficilis, Desh. solenella, Desh. 



elongata, Lam. tenuis, Desh. 



Layardi, Desh. violacea, Lam. 



luuulata, Desh. virescens, Desh. 

 minor, Desh. 



Sub-gen. psammotella, Deshayes. 



Shell thin, covered with an epidermis ; hinder side rounded, 

 not rostrate. 



ambigua, Desh. Philippinensis, Desh. 



oblonga, Desh. rubra, Chem. 



Malaccensis, Desh. subradiata, Desh. 



Genus ELIZIA, Gray. 



Shell sub- orbicular, equivalve, compressed, thin; surface 

 of valves covered with a hard, shining epidermis; beaks 

 sub-anterior, not prominent. Hinge with the primary teetli 

 oblique, two in the right valve, the hinder elongate and 

 bifid ; three in the left valve, the central bifid. Pallial line 

 sub-marginal ; siphonal inflection deep, oblong, proceeding 

 from the upper part of the hinder margin to the centre of 

 the valves. 



Ex. E. orbiculata, Wood, -pi. 103, fig. 5, 5, a. 



The animal of this genus is unknown ; the shell on 

 which it is founded is the So/eu orbiculaius of Wood. 



