10 CO^CRYLIA—DITHYRA. 1. 



margin of the hinge on the inside of each valve just over the 

 teeth ; the accessorial valve at the back is lanceolate, being pro- 

 duced to a point at both ends. 



Candida. Pholas testd obovatd, latere antico suhclauso obtuso, valvd altera 

 lamina ciirvd marginali supra dentem, accessorio unico cardinali. 

 Shell oboval, obtuse and nearly closed at the anterior end, with 

 a curved lamina in one valve above the tooth, and a single ac- 

 cessorial valve at the hinge. 



Pholas Candida. Linn. Syst. Nat. p. 1111. 



Gmelin, Syst. p. 3215. 



Turton, Linn. Syst. iv. p. 173. 



Pennant, Brit. Zool. iv. p. 156, tab. 42, fig. 2. 



Da Costa, Brit. Conch, p. 246. 



Chemnitz, \in. p. 358, tab. 101, fig. 861 and 862. 



Montagu, Test. Brit. p. 24. 



Donovan, Brit. Shells, iv. tab. 132. 



Linn. Trans, viii. p. 31. 



Turton, Brit. Fauna, p. 145. 



Wood, Conch, p. 79, tab. 14, fig. 3 and 4. 



Dillwyn, Descript. Catal. p. 36. 



Turton, Conch. Diet. p. 144, fig. 79. 

 Pholas parvus. Lister, Conch, tab. 453, 278. 

 Mus. nost. Inhabits marine rocks. 



Shell about an inch long, and nearly two wide, extremely thin 

 and almost transparent, with rather remote prickly striae at 

 the larger end; and may be distingui.shed by the larger end 



