92 THE NAUTILUS. 



Pupoides marginata Say. 



Gastrodonta liyera Say. 



Vitrea indentata Say. 



Physa gyrina Say. In a small pond by the side of the railroad 

 track. 



From a pile of mussel shells left by a pearl- hunter I noted seven- 

 teen or eighteen species. 



Kemmswick, Jefferson County. 



Polygyra appressa Say. A search by the railroad and on the 

 bluff above gave a single dead shell of this species, but no other. 



Washington County. 



Here we are getting away from the limestone formations, and 

 shells are scarce. 



Polygyra fraterna alicice Pils. Mineral Point. 



Bifidaria armifera Say. Potosi. 



Pupoides marginata Say. Potosi. 



Zonitoides arboreus Say. Mineral Point. 



Zonitoides minusculus Binn. Potosi. 



Vitrea indentata Say. Potosi and Mineral Point. 



Pltysa gyrina Say. In a spring branch at Potosi. In a large 

 stream close by no shells were found. A swift-flowing clear stream 

 at Mineral Point did not show any shells. 



Ironton, Iron County. 



Polygyra albolabris alleni Weth. A single dead shell was found 

 on Shepard's Mountain adjoining the town. The other land shells 

 were found at the same place. 



Polygyra inflecla Say. The umbilicus of the single shell found 

 was not covered. 



Polygyra dorfeuilliana Lea. 



Zonitoides arboreus Say. 



Physa gyrina Say. In a spring branch. In a larger stream close 

 by no shells were found. 



St. Francois County. 



Polygyra thyroides Say. Farmington and Rivermines, the latter 

 to 25 mm. diameter. 



