MY A. 53 



p. 181. t. 9. f. 3. Chemnitz, vi. p. SI. 

 I'm, p. 3221. Wood's Conch, p. 108. 

 Mya, No. 8. Schroeter Einleitung, ii. 

 Unio. Enc. Method, t. 248. f. 8. 



Inhabits rivers in Coromandel. Muller. Tranqnebar. Schroe- 

 ter. 



Shell from eight to eleven lines long, and from eleven to sixteen 

 broad, of a grass-green colour, variously shaded with yellow, 

 and marked with elevated wrinkled stria? about the hinge ; it 

 is thin, pellucid, and radiated in the inside ; the teeth resem- 

 ble those of M. pictorum. Muller appears to have consi- 

 dered the distance between the beak and the opposite mar- 

 gin to be the breadth of the shell, and has thus inverted the 

 usual mode of measuring bivalves. Gmelinhas retained this 

 error in those species which he has copied from Muller, al- 

 though in most other instances he has followed the opposite 

 method, and has thus introduced a good deal of confusion 

 with regard to the dimensions of bivalves. 



Schroeter, in the Fluss. Conch., has described a shell allied to 

 the present species under the name of Mya rhomboidea, but 

 I cannot find that it has been noticed by any other author, or 

 by himself in the Einleitung, so that he probably afterwards 

 ascertained it to be undeserving of further attention. 



HUGOSA. 31. Shell oval, wrinkled ; primary teeth of 

 the hinge crenulated ; lateral teeth long, and 

 in one valve double. 



Mya rugosa. Gmelin, p. 3222. Wood's Conch, p. 109- 

 Mya corrugata magna. Chemnitz, x. p. 346. t. 170. 

 f. 1649- 



Variety. Smooth at the beaks. 

 Mya, No. 9. Schroeter Einleitung, ii. p. 6 17. t. 7. f. 5. 

 Mya spuria. Gmelin, p. 3222. Wood's Conch, p. 110. 

 Unio. Enc. Method, t. 249. f- 3. 



Inhabits rivers in Coromandel. Chemnitz. 



Shell about an inch long, and rather more than an inch and a 

 half broad ; it is greenish, and prettily wrinkled on the out- 

 side ; the inside is pearly. Gmeliu's M. spuria is said by 

 Schroeter to inhabit the rivers of Tranquebar, and is most 

 probably a variety either of this or of the preceding species, 

 which are very nearly allied. 



variabilis. 32. Shell sub-rhomboidal, gibbous, 

 and longitudinally wrinkled at the beaks ; 



