Notes on Species of Corbiculadce. 225 



Hob. — In fluviis Umpingano, Gauritz, Lepenulla et Caput 

 Natal, Africae Meridionalis. Collect. Mns. Stuttgardt ; Mns. 

 Stockholm et Prime. 



The shell is orbicular, trigonal, compressed, and nearly equi- 

 lateral. The anterior side is broader and more obtuse. The 

 striae are close and regular. The epidermis is of a light green- 

 ish olive color and polished. The interior of the valves is pur- 

 plish-violet. The beaks are small, acute, and somewhat raised. 

 The lunula is a little lighter in color than the rest of the shell. 



The original describer of this species, Dr. Krauss, is in error 

 in referring it to the Corb. radiata and pusilla, as may be seen 

 by a comparison of the Corb. Africana with these species. The 

 Corb. pusilla is more globose, more trigonal, it is smaller, the 

 coloring is different, the beaks are much fuller, and the hinge 

 is much broader and more curved. The Corb. radiata is small- 

 er, more globose, less trigonal, the coloring is not the same and 

 the hinge is more rounded. 



44. Corbicula ducalis, Prime. 



Cyrena ftuminea, Mousson. Moll. Java, 87, pi. xx. f. 3. 1848. 



Philippi. Abbild. II. 76, pi. 1, f. 3. 1847. 

 Corbicula ducalis, Prime. Bost. Soc. Nat. Hist. Proc. viii. 274. 1862. 



Prime Cat. 4. 1863. 



C. testa ovato-trigona, oblique inaequilaterali, tumida, utraque extre- 



Fig. 58. 



Corbicula ducalis. 



mitate aequaliter obtusa ; epiderrnide olivaceo-flava, nitente vestita ; striis 



