50 MYA. 



Mya pictorura. Linnceus Sgst. Nat. p. 1112. Mutter 



Hist. Verm. p. 212. Pennant Zool.'w. p. 79- t. 43. 



f. 17. Da Costa Brit. Conch, p. 228. t. 15. f. 4. Born. 



Mm. p. 20. Schroeter Einl. ii. p. 604. Gmelin, p. 3218. 



Maton and Racket in Lin. Trans, viii. p. 38. Dorset 



Cat. p. 28. I. 12. f. 4. Wood's Conch, p. 104. t. 19. f. 3 



and 4. 

 Mya angustata, &c. Schroeter Fluss. p. 184. t. 3. f. 3. and 



t. 4. f. 6. 

 Mya ovalis. Pidteneys Dorset, p. 27- Donovan, iii. t. 89- 



Montagu Test. p. 34. 

 Bonanni Rec. 2. f. 40. .Lis*, ^m'm. Ang. t. 2. f. 30. and 



Conch, t. 147. f. 3. Prfroer Gaz. t. 93. f. 9. Enc. 



IfeM. t. 248. f. 4. 

 Common in the rivers of Europe. 



Shell an inch and a half, or two inches, long, and from three 

 to four inches broad, of a dusky green colour, marked with 

 concentric wrinkles ; it is more pointed on one side, and is 

 rather longer in proportion to the breadth than M. Batava, 

 which, as well as M. ovata, has however been considered by 

 Muller to be only a variety of this species. Solander's de- 

 scription of M. pictorum appears from his MSS. in Sir Jo- 

 seph Banks's library, to have been taken from the present, so 

 that the error has probably originated with Dr. Pulteney. 



ovata. 24. Shell ovate, thick, and narrower on the 

 anterior side. 



Mya ovata. Donovan, iv. t. 122. f. 1 and 3. Maton and 

 Racket in Lin. Trans, viii. p. 39. Wood's Conch, p. 105. 

 t. 19. f. 5. 

 Lister Anim. Ang. App. f. 6. Conch, t. 147. f. 2. 



Variety. Shell depressed in the middle. 



Mya depressa. Donovan, iii. t. 101. and iv. t. 122. f. 2. 



Inhabits the rivers of England. Lister, fyc. 



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

 and a quarter broad, of a greenish brown colour, striated 

 concentrically, and sometimes marked with paler longitudi- 

 nal rays. It is thicker and more ponderous, but so nearly in 

 other respects approaches M. pictorum, that it has been con- 

 sidered to be only a variety by Muller, Solander, and Mon- 

 tagu. Donovan's M. depressa has no claim to be consider- 

 ed a separate species, and Schroeter has described a shell, 

 which may probably be another variety; see Fluss. Conch. 

 p. 181. t. 9. f. 1. and Einleitung, ii. p. 621. No. 18. where 

 in the former work it is said to be a native of Greenland, and 

 in the latter, of Tranquebar. 



