244 



BIBLIOGRAPHY OF 



Purpura lapillus Linn. 

 Sanguinolaria fusca Say. 

 Saxicava distorta Linn. 

 Scalaria Greenlandica 



( 'h i in n . 

 Sigaretus haliotoides Linn. 

 Skenia serpuloides Mont. 

 Solemya borealis Totten. 



velum Say. 

 Solen ensis Linn. 



siliqua. 

 Terebratula caput-ser- 



pentis Linn. 

 Tnracia truncata Mighels. 

 Trichotropis borealis Sowb. 

 Turritella erosa ( 'outh. 

 Velutina laevigata Linn. 



zonata Gould. 

 Venus gemma Totten. 



mercenaria Linn. 



FRESH-WATER SHELLS. 



Alasmodon arcuata Barnes. 



marginata Say. 



undulata Say. 

 Amnicola lustrica Say. 



porata Say. 

 Ancylus rivularis Say. 



tardus Say. 

 Anodon cataracta Say. 



implicata 



marginata Say. 

 Cyclas calyculata Drop. 



minor Might is. 



partumeia Say. 



similis Say. 

 Limnaea columella Say. 



decollata Mighels. 



desidiosa Say. 



humilis Say. 

 Paludina decisa Say. 

 Physa ancillaria Say. 



heterostropha Say. 



hypnorum l>rap. 



