LIST OF THE SNAILS COLLECTED 95 



VIII. LIST OF MOLLUSCA OF HARDING AND PERKINS 



COUNTIES.* 



Collected by Win. H. Over and Determined by Dr. H. A. Pilsbry 

 of Academy of Natural Sciences, Philadelphia, Pa. 



Lymnaea bulimoides cockerelli Pils & Fer. Common in water- 

 holes. 

 Lymnaea palustris Mull. The most common freshwater shell in 



state. 



Lymnaea Caperata Say. In waterholes, not abundant. 

 Lymnaea bullimoides var. techella Hald. Near Camp Crook. 

 Lymnaea humilis var. modicella Say. Spring-holes in East Short 



Pine Hills. 

 Lampsilis luteolus Lamk. Rare, only one specimen collected in 



Little Missouri river at Camp Crook. 

 Anodonta grandis Say. Several seen in North Grand river, near 



Grand River, P. O. 



Physa sayi Tapp. Springholes in West Short Pine Hills. 

 Physa gyrina Say. Near Antelope Creek. 



Physa integra Hald. Little Missouri river north of Camp Crook 

 Planorbis exacuos Say. Antelope creek, Perkins county. 

 Planorbis deflectus Say. Antelope creek, Perkins county. 

 Planorbis trivolvis Say. Waterholes 7 miles north of Camp Crook. 

 Planorbis tinidus Pfr. Antelope creek. 



Planorbis umbilicatellus C'k'll. Waterholes near Rabbit Butte. 

 Euconulns fulvus Mull. Damp shady places in Slim Buttes. 

 Succinea avara Say. Floodplain Little Missouri River at Camp 



Crook. 

 Succinea grosvenorii Lea. Collected from under sagebrush and 



cacti. The most abundant land shell in the plains country. 

 Pisidinm contortum Ptime. Springs in Slim Buttes. 

 Musculium jayense Prime. Waterholes near Sorum. 

 Sphaerium striatum var. acuminatum Prime. Little Missouri 



River. 

 Vallonia gracilicosta Reinh. Camp Crook and West Short Pine 



Hills. 



*As Perkirvs County joins Harding- on the east and the topography is 

 nearly identical, it is probable that all specimens listed from Perkins 

 could be found in Harding County. 



