8 THE MOLLUSCA OF MUSCATINE COUNTY. 



the State. It was common, or almost abundant, at the place 

 mentioned above, some three years ago. Length, 5.6 mm. 



PUPA. 



P. pentodon, SAY. Rare. About old logs and leaves where it is 

 damp. 



P. fallax, SAY. Ven 7 rare. Appears to be confined to a space 

 scarcely more than ten feet square in a woodland about one 

 mile above Muscatine. 



P. armifera, SAY. Widely dispersed. Prefers loam among grass- 

 roots about stumps and logs in woods. Common. 



P. contracta, SAY. Common. Found with armifera. 



SUCCINEA. 

 S. ovalis, GOULD. Very abundant in swamps. Associated with 



Limnece. Shell very thin. 

 S. avara, SAY. Rare. Two forms are found here, one, extreme 



length, mm., and seems to live in the ground ; the other, 



mm. long, and has about the snme habit as S. obliqua. 

 S. obliqua, SAY. Abundant on Geneva Island with H. multiline- 



ata. Shell much stronger than ovalis. They do not seem to 



be hermaphrodite. 



PHYLOMYCIDJE. 



TEBENNOPHORUS. 



T. carolinensis, Bosc. Common. In woods about old deca}-ing 

 stumps and logs. Easily found on warm, damp days. The 

 same may be said of all our land-mollusks. 



AUBICULIDJS. 



CARYCHIUM. 



C. exigumn, SAY. Common. This minute mollusk is wide-spread ; 

 is found under damp, decaj^ing leaves in woods. 



LIMNEID^S. 



LIMNEA. 



L. reflexa, SAY. Abundant in nearly all of our ponds ; and there 

 are almost as many different forms as ponds. Near West 



