MACTRA. 147 



Mactra hians. Solander's MSS. Pulteney's Dorset Cat. 



p. 32. Montagu Test. p. 101. Donovan, iv. t. 140. 



Maton and Racket, in Lin. Trans, viii. p. 74. Dorset 



Cat. p. 33. t. 2. f. 4. 



Mya oblonga. Chemnitz, vi. p. 27. t. 2. f. 12. Gmelin, 



p. 3221. 

 Mya, No. 3. Schroeter Einl. ii. p. 6 1 5. 

 Chama magna. Da Costa Brit. Conch, p. 230. t. 17. f. 4. 

 Lutraria solenoides. Lamarck Syst. des Anim. p. 120. 

 Gualter, t. 90. f. A. |L 



Inhabits the coasts of Britain. Da Costa, fyc. 



Shell about two inches and a quarter long, and rather more than 

 half as broad, strong, rugged, of a dark brown colour, fre- 

 quently tinged with red or cinereous, covered, when recent, 

 with a thick dusky epidermis, and marked with irregular wrin- 

 kled concentric striae ; the hinge is placed considerably on the 

 posterior side of the centre, and has a grooved flattish tooth 

 locking between two others in the opposite valve ; the valves 

 do not shut quite close at the posterior end, and the anterior 

 gapes very considerably, and is somewhat patulous ; the up- 

 per margin on the anterior side of the hinge being incurved, 

 serves to distinguish this species readily from M. lutraria. 



l a 



