730 



The concentric ribs of this s])ecies are more obtuse, less elevated, 

 and less strongly crenulated than those of V.crenulata ; while 

 the general form is more elevated, the sides more sloping, and 

 the terminations more acuminated. The Imiule is smooth and 

 large. 



West Columbia. Cnmlng. 



79. Venus gallinula (pi. clxii. f. 225, 226), Lamarck, 

 Anim. sans vert.; Delessert, t. 10. f. 3. V. costulata. Wood's Sup- 

 plement, t. 2. f. 15. 



V. testa oblonga, ventricosa, postice subangulata, subtruncata, 

 antice breviuscula, quadratim subrotundata, albida, fusco angula- 

 tim lineata, intus violacea, costellis prominulis subtus crenulatis 

 laminatis cincta; margine dorsali paululum declivi, subdepresso; 

 lunula parva, striata, ovali ; margine intus crenulato. 



Although similar in the character of the ribs, this shell differs 

 widely from V. cremdata, being of a more oblong, truncated form, 

 having the dorsal area less distinct, and the lunule small. 



New Holland. 



80. Yenus foveolata (pi. chv. f. 46), Sowerbi/,jun. 



V. testa lenticular!, compressiuscula, alba, postice fulvo pallide 

 tincta, latninis concentricis numerosis acutis cincta ; margine dor- 

 sali profunde excavate, subplanulato ; lunula magna, cordiformi, 

 impressa, substriata ; margine interno crenulato. 



Of a lenticular form, white, with a shade of pinkish-brown at 

 the back ; the laminae are very numerous and sharp-edged ; the 

 dorsal area forms a deep, elongated, smooth-sided pit, from wdiicli 

 I name the species ; the lunule is large ; inner margin crenulated. 



Martinique. 



81. Venus declivis (pi. clvii. f. 123, 124), Sowerly,jun. 



V. testa ovali, subcordata, albida, immaculata vel pallide viola- 

 ceo literata, intus pallide rosea, laminis concentricis distantibus pro- 

 minulis et striis intermediis elevatis cincta; latere postico sub- 

 acuminato, declivi; margine dorsali planulatim excavato, irregu- 

 lariter et sparsim lineato; lunula impressa, cordiformi; margine 

 interno crenulato. 



Eather small ; tending to heart-shaped oval, girt wdtli elevated, 

 sharp, distant laminse and intermediate raised stria3 ; dorsal edge 

 sloping, smooth, deeply excavated, and sparingly lineated, even 

 A\hen the shell is otherwise white. The purple-marked variety 

 slightly differs in appearance from the others in the rather less 



