228 PNEUMONOBRANCHIATA. 



Auricula alba. Gray, Ann. Philos. 15.; Jeffreys, 

 Linn. Trans, xvi. 370.; Forbes, Malac. Monen. 

 12. 



Volvaria alba. Fleming. 



Inhab. sea-coast near the mouths of rivers, under 

 stones left by the tide. 



The animal pellucid white. 



When alive, the shell is milk-white, with the spire 

 reddish, with a pellucid spiral line about half the 

 breadth of the whorl from the suture. 



Dr. Fleming, evidently from not knowing the 

 species, refers C. denticulata to Acteon, and C. albus 

 to Volvaria, both being genera of Ptenobranchous 

 Mollusca. 



