NATURAL SCIENCES OE PHILADELPHIA. Ill 



Helix indentata, Say. 



Blount, Knox, and Monroe Counties. Very rare. 

 Helix infleeta, Say. 



A common species accidentally omitted in previous papers. 

 Helix lasmodon, Phillips. 



Besides the usual depressed form, Miss Law reports a single 

 .specimen, elevated like some of the varieties of gularis. 

 Helix ligera, Say. 



A few well characterized specimens from Monroe County, larger 

 and paler than Ohio shells. 



Helix Mitchelliana, Lea. 



A single shell. (See H. clausa.) 



Helix profunda, Say. 



A single dead shell found on a bluff in Roane County. 

 Helix sculptilis, Bland. 



Monroe County. Yery scarce. 

 Helicina orbiculata, Say. 



Byrd's Bluff, Roane County. Somewhat abundant. 



Succina avara, Say. 

 Single specimen only. Monroe County.. 



OPEECULATED AQUATIC UNIVALVES. 

 Trypanostoma aratum 1 Lea, or bicinctum, Tryon. 



Holston River. Scarce. 

 Trypanostoma glandulum, Anth. Mel. glans, Anth. 



Holston River. This will, I think, prove to be a young Stre- 

 phobasis. 

 Trypanostoma robustum, Lea. 



Holston River. 

 Trypanostoma Troostii, Lea. 



Holston River. 



The species that follow are mostly from small streams and 

 springs, to which frequent references will be made ; and to save 

 space the various stations are here tabulated, and references made 

 to them (in remarks on species), by numbers. 



[Numbers on the right refer to species associated, locally.] 



