CO^CRYLIA—DITHYRA. 53. 239 



under the ligament on the anterior side, which terminates in a 

 depression. Ligament external. 



Anodon testa ovatd tumicld inasquilaterali, margine arcuato, latere Cygneus. 



antico angustato acuminato. ^• 



Shell oval tumid inequilateral, arcuated at the margin, with the 



anterior side narrowed to a point. 

 Mytilus Cygneus. Liym. Syst. Nat. p. 1158. 

 Gmelin, Syst. p. 3355. 

 Turton, Linn. Syst. iv. p. 293. 

 Pennant, iv. p. 239, tab. 70. 

 Da Costa, p. 214, tab. 15, fig. 2. 

 Chemnitz, viii. p, 185, tab. 86, fig. 762, 

 Donovan, British Shells, ii. tab. 55. 

 Montagu, Test. Brit. p. 170. 

 Linn. Trans, viii. p. 109. tab. 3. A. fig. 2. 

 Turton, British Fauna, p. 1 65. 

 Dorset Catal, p. 40, tab. 12, fig. 42. 

 Dillwyn, Descript. Catal. p. 315. 

 Turton, Conch. Diet. p. 115. 

 Musculus latus. Lister, Conch, tab. 156, fig. 11. 

 Mus. nost. Common in rivers, ponds, and canals. 



Shell growing to two or three inches long, and six or seven broad, 

 green or pale brown, wrinkled or striate transversely, produced at 

 the anterior side to a rather pointed termination, with the margin 

 opposite the hinge curving outwards : beaks minute, with the region 

 about them sometimes decorticated. 



