238 CONCHYLIA— D/THYi?^. 53. 



ostreoides. DiSCINA 



Discina ostreoides. Lamarck, Syst. vi. \). 237. 

 Orbicula Norwegica. Lamarck, Syst. p. 242. 

 Patella anomala. Gmelin, Syst. j). 3721. 



Turton, Linn. Syst. iv. p. 585. 

 Anomia turbinata. Dillwyn, Descript. Catal. p. 2S6. 

 Patella distorta. Montagu, in Linn. Trans, xi. p. 195, tab. 13, fig. 5. 



Turton, Conch. Diet. p. 140. 

 Mus nost. Attached to submarine stones. 



Shell hardly half an inch in diameter, i-ather fiat, rugged and 

 very irregular in the circumference; the upper valve brown, with a 

 small wart-like protuberance which is not quite central ; inside mi- 

 nutely granulate : the under valve thin, Avhite or blueish white, and 

 attached to submarine stones. 



53. A'^ODOl^— LAMARCK. 



Testa transversa, cequivalvis, incBquilateralis, lateribus subhiantibus. 



Cardo edentulus, lamina transversa, anticd sinu terminatd. Liga- 



inentum. externum. 



Shell transverse, equivalve, inequilateral, a little ojjen at the 

 sides. Hinge without teeth, furnished with a transverse lamina 



