Notes on Species of Corbiculadce. 



219 



The accompanying drawing, Fig. 49, represents a true and 

 constant variety of this species, which differs from the type in 



Fig. 40. 



Corbicula Cumingii (varietas). 



being less transverse and much more inflated, the beaks are also 

 more convex and the striae are more remote. 



36. Corbicula tlllllida, Deshayes. 



Corbicula tumida, Deshayes. Proc. Zool. xxii. 343. 1854. 

 Biv. Brit. Mus. 229. 1854. 

 „ Prime Cat 4. 1863. 



C. testa regulariter ovato-transversa, tumida, tenui, subsequilaterali ; 

 postice paulo longiore, utraque extremitate aequaliter 

 obtusa ; umbonibus parvis, turgidulis, incurvis; valvis 

 intus violaceis ; striis regularibus valde distantibus; epi- 

 dermide viridi, nitente vestita ; cardine angustissimo. 



Long. 17 ; lat. 13 ; diam. 10 mill. 



Hab. — Borneo. Collect. Mus. Brit., Cuming et Prime. 



Corb. tumida. 



The shell is transversely-oval, inflated, and nearly equilateral. 

 The posterior side is a little the longer. Both lateral margins 

 are obtuse. The beaks are small, but full, and they curve 

 inwardly. The color of the interior is violet. The striae are 

 regular and very distant. The epidermis is green and polished. 

 The hinge is very narrow and slight. 



This species is allied to Corb. occidens and Cumingii. Com- 

 paring it with the form of Corb. Cumingii described as Corb. 

 notata (Fig. 48), we find that it differs in being smaller, less 

 transverse, and more tumid, the beaks are fuller, the sides are 



