THE NAUTILUS. 91 



Vallonia parvula Sterki. Clay, Deuel and Brule Counties. 

 Valtonia gracilicosta Reinh. Common over the State. 

 Vallonia perspectiva Sterki. Deuel Co. 



Oreohelix cooperi W. G. B. Spearfish Canyon, Lawrence Co. 



Polygyra, munodon Rack. Woods along Vermilion River, Clay 

 Co. 



Pupoides marginatus Say. Common in the semi-arid districts. 

 Also Clay Co. 



Pupoides inornatus Vanatta. Type lot from drift along White 

 River, Washington Co. Also collected along Indian Creek, 

 eastern Pennington Co. 



Bifidaria tappaniana Ads. Clay and Deuel Counties. 



Bifidaria clappi Sterki. Pennington Co. 



Bifidaria holzingeri Sterki. One specimen taken in woods 

 along Spearfish Creek in Lawrence Co. 



Bifidaria agna Pils. and Van. Quite general over the State. 



Bifidaria contracta Say. Clay Co. 



Bifidaria procera Gld. All through the southern part of State. 



Bifidaria ami/era Say. Common over the State. 



Bifidaria armifera abbreviata Sterki. Perkins Co. 



Bifidaria pentodon Say. Over the State. 



Pupilla muscorum L. Washington Co. 



Pupilla blandi Morse. Pennington and Brule Counties. 



Vertigo ovata Say. Deuel and Clay Counties. Probably 

 common in eastern part of State. 



Vertigo milium Gld. Found in drift along Missouri River at 

 Chamberlain, Brule Co. 



Cochlicopa lubrica Mull. Clay, Lawrence and Deuel Counties. 



Vitrina alaskana Dall. Lawrence Co. 



Polita hammonis Strom. Clay, Deuel and Pennington Coun- 

 ties. 



Euconulus fulvus Mtill. Pennington. Lawrence, Harding and 

 Deuel Counties. 



Zonitoides arbor ea Say. Locally over the State. 



Zonitoides minusada Binn. Common over the State. 



Zonitoides nitida Miill. Clay, Deuel and Washabaugh Counties. 



Zonitoides singleyana Pils. Brule, Clay and Custer Counties. 



Agriolimax campestris Binn. Harding Co. Probably in eastern 

 part of State. 



