134 MACTRA. 



Gualter, t. 85. f. F. Ktwrr, vi. t. 34. f. 1. Enc. MetL 

 t. 251. f. I. 



Inhabits the Mediterranean. Linnaus. West Indies. Muller. 

 Coasts of Coromandel. Chemnitz. Naples. Ulysses. 



Shell about two inches long, two and three-quarters broad, and 

 an inch and a quarter high, and sometimes considerably 

 larger ; it is white, rather pellucid, and plaited transversely 

 towards the umbones ; the hinge is placed rather nearer the 

 posterior than the anterior end, and the valves do not shut 

 quite close at the latter. 



cygnea. 6. Shell ventricose, slightly wrinkled 

 transversely, and truncated at the anterior 

 end ; posterior slope heart-shaped, and finely 

 striated. 



Mactra cygnea. Chemnitz, vi. p. 217. t. 21. f. 207. 

 Mactra cygnus. Gmelin, p. 3260. 

 Mactra, No. 1. Schroeter Einl. iii. p. 80. 



Inhabits the coasts of Tranquebar. Chemnitz. 



Shell about one inch long, and fourteen lines broad, very ven- 

 tricose and triangular, and white without any coloured mark- 

 ings. 



maculata. 7. Shell gibbous, brittle, smooth, irre- 

 gularly spotted, slightly angulated at the an- 

 terior, and rounded at the posterior end ; pos- 

 terior depression heart-shaped. 



Mactra maculata. Chemnitz, vi. p. 217. t. 21. f. 208 and 

 209- Gmelin, p. 3260. 



Mactra, No. 2. Schroeter EinJeitung, iii. p. 81. 



Enc. Meth. t. 254. f. 3. 

 Inhabits the coasts of the Nicobar Islands. Chemnitz. 

 Shell about an inch and three-quarters long, two inches and a 



quarter broad, and an inch and a quarter high ; thin, brittle, 



pellucid, white, and marked with irregular scattered chestnut 



spots ; the inside is white and finely striated. 



turgida. 8. Shell ventricose, thin, with the um- 

 bones incurved, remote, and purplish ; inside 

 finely striated longitudinally. 



Mactra turgida. Gmelin, p. 3260. 



Mactra tumida seu inflata. Chemnitz, vi. p. 218. t. 2J. f. 

 210 to 212. 



