82 THE NAUTILUS. 



bodies of standing water in the county are small, and with one or 

 two exceptions are artificial ponds. Horseshoe Lake and Lake 

 View are natural basins but both are small and contain but few 

 moUusks. The small streams emptying into the Kansas River con- 

 tain a few shells very locally distributed. The River is too sandy 

 for these animals. 



The family Ancylidce seems not to have a representative in these 

 waters. 



Very little collecting previous to 1908 has ever been done in 

 Douglas County. Polygyra m. chadwicki, a dentate variety of 

 Polygyra multilineata was described by Ferriss in the Nautilus for 

 August, 1907, from specimens collected along the Kansas River at 

 Lawrence. Aside from this one reference I have never found the 

 shells of this county alluded to. Therefore I append the following 

 list, based upon two years' collecting in which the entire county has 

 been thoroughly searched. Probably not many more species will be 

 collected. Four or five are withheld from this list because of un- 

 certain identification. 



Dr. V. Sterki has examined the Piipidce, and Mr. F. C. Baker, 

 the Lymneas, to both of whom I am very grateful. 



Polygyra profunda Say. 



Polygyra albolabris alleni Wetherby. 



Polygyra multilineata Say. 



Polygyra multilineata chadwicki Ferriss. 



Polygyra divesta Gould. A single specimen found in drift along 

 the Kansas River at Lawrence. 



Polygyra clausa Say. With the exception of P. profunda and P. 

 albolabris alleni, which range into Shawnee County on the west, 

 Douglas County marks the extreme western range of the Mesodons. 

 All the species are rare in this locality, and are found on the north- 

 ern shaded slopes of hillsides which have limestone outcropping. 



Polygyra dorfeuilliana Lea. Dead shells were found under condi- 

 tions such that the species must be living here. 



Polygyra monodon Rackett. This form lives on Blue Mound. 



Polygyra fraterna Say. The common Polygyra of Kansas. 

 Found everywhere. 



Polygyra fraterna aliciee Pilsbry. Occasionally found with P. 



fraterna. 



{To be continued.) 



