352 



THE CHICAGO ACADEMY OF SCIENCES. 



British America. 

 Ontario: Pic Lake, Thunder Bay Di>trict (Agassiz; Dall ; Gould); Lake 

 Superior (Gould); Ottawa, Carleton Dist. (Latchford; Taylor). 

 Geological Distribution : Unknown. 



Ecology : In Tomahawk Lake, Wisconsin, this species lives in 

 swampy or quiet bays or pond-like bodies of water connecting with 

 the lake. In quiet bays it may be found rarely on the sandy shore 

 in shallow water. Its more usual habitat is in swampy areas where 

 'there is a quantity of vegetation such as Typha and the pond scums, in 



too is 



9C tO 



75" TO 



Fig. 41. 



which situation it may be found on floating logs or in the vegetation. 

 In this region it is typically an inhabitant of swampy, Typha bordered 

 bogs, in which there is an accumulation of old logs. 



Remarks: Lanccata is one of the Lymnaeas which has been much 

 misunderstood for many years. By several authors it has been con- 

 sidered a synonym of kirtlandiana and cxilis. Dr. Dall in his excellent 

 report on Alaska Mollusks, page 72, refers it to kirtlandiana as an 

 immature form. An examination of a cotype in the Smithsonian col- 

 lection, and a study of Gould's figures and descriptions, aided by a 

 collection of over one hundred specimens from the northern states 

 shows that it is a good species. It is true that Binney's figure is very 

 poor, but the two figures in Agassiz's Lake Superior (pi. 7, figs. 8 



