27 



the circular margin of the shell, but less finely and regit* 

 larly than the former. 



Of this shell also, I have seen but a single valve, obtained 

 from the byssus of a Pinna from deep water. 



VENUS. 



GENERIC CHARACTER: The shell with the valves 

 equal, sides unequal, transverse or suborbicular. Three 

 approximate cardinal teeth in each valve; the lateral teeth 

 diverging at the summit, ligament external, covering the 

 scutcheon. 



V. CASSINA. V. Erycina, variety. Pen. Brit. Zo., vol. 

 4, pi. 54, fig. 48. V. C. Flem. Brit. An,, p, 446. Not 

 common. 



* V. VERRUCOSA. Turt. Lin. V. Erycina. Pen. Brit. 

 Zo., vol. 4, pi. 54, fig. 48. V. V. Mont. Test. Brit., 

 vol. 1, p. 112. Borlase's Nat. Hist. Corn. pi. 27, fig. 32. 

 Flem. Brit. An,, p. 446. Common on the shores east of 

 the Lizard, and abundant in the soil dredged from 

 Falmouth harbour. 



* V. FASCIATA. V. Paphia. Turt, Lin. Mont. Test. 

 Brit., vol. 1, p. 110. V. F. Flem. Brit. An., p. 447. 

 Common. It frequently creeps into crabpots in search of 

 the bait. 



* V. GALLINA, Turt. Lin. V, Striatula. Mont. Test. 

 Brit., vol. 1, p. 113. V, G. Flem. Brit. An., p. 448. 

 Common ; and with the same habits as the last. 



V. SUBCORDATA. Mont. Test. Brit., vol. 1, p. 121, 

 pi. 3, fig. 1. Flem. Brit. An., p. 447. Found by Mon- 

 tagu in sand from Falmouth harbour. 



V. GRANULATA. Turt. Lin. Mont. Test. Brit., vol. 1, 

 p. 122. Flem. Brit. An., p. 447. Scarce; found by 

 Montagu at Falmouth. 



V. UNDATA. Turt. Lin. Pen. Brit. Zo., vol. 4, pi. 55, 

 fig. 51. Mont. Test. Brit., vol. 1, p. 117. Flem. Brit. 

 An., p. 448. Not common. Montagu found it at Fal- 

 mouth. 



* V. AUREA. Turt. Lin. Mont. Test. Brit., vol. 1, 

 p. 129. Flem. Brit. An., p, 449. This shell seems to 

 be locally common. Montagu found it in sand from Fal- 

 mouth harbour; from whence also I have obtained it, and 

 from St. Austle bay. 



CARD I ACE A. 

 Cardinal teeth irregular, either in form or situation, and 

 generally accompanied by one or two lateral teeth. 



CARDIUM. 



GENERIC CHARACTER: Shell with equal valves, some- 

 what heart shaped; beaks prominent; internal margin of 



