68 CO^CH\L\A—DITHYRA. 23. 



Mactra solida. Litin. Syst. Nat. p. 1 126. 



Gmelin, Syst. p. 3259. 



Turton, Linn. Syst. iv. p. 211. 



Pennant, iv. p. 193, tab. 55, fig. 2. 



Chemnitz, vi. p. 230, tab. 23, Hg. 229, 230. 



Donovan, British Shells, ii. tab. 61. 



Montagu, Test. Brit. p. 92. 



Linn. Trans, viii. p. 70. 



Turton, British Fauna, p. 154. 



Dorset Cafal. p. 32, tab. 6, lig. 6. 



Diihcyn, Descript. Catal. p. 140. 



Turton, Conch. Diet. p. 81. 

 Trigoneila Gallina. Da Costa, p. 199, tab. 14, fig. 6. 

 Mus. nost. On most sandy coasts. 



Shell an inch and a half long and two inches broad, strong and 

 solid, nearly smooth or with a few antiquated ridges, equally 

 sloping obliquely at the sides so as to make the front margin 

 longer than the lateral angles : color yellowish-white, often 

 marked with deeper transverse zones. 



tnincaia. Mactra testd trigonu la^viusculd cequilaterali, lateribus trun- 

 catis, umbonihus jyoductis rectis. 

 Shell triangular nearly smooth and equilateral, with the sides 



truncated, and the beaks elongated and straight. 

 Mactra truncata. 3Iontagu, Test. Brit. Suppl. p. 34. 



Pennant, Brit. Zool. iv. p. 196, tab. 54, 



fig. 1. 

 Dorset Catal. p. 34, tab. 12, lig. I. 



