330 WALKER: SHELLS OF MICHIGAN. 



description has ever been published. It is related to S. ovalis, 

 Gld., but is apparently very distinct. 



Succinea avara Say. 



S. obliqua Say. 



S. campestris Sa}^ Sager, Miles. As this species is 

 strictly a southern one, the citation is undoubtedly erroneous. 

 Some form of 6". obliqua is probably referred to. 



Carychium exiguum Say. 



Limnaea stagnalis L. 



L. arnpla Migh. 



L. decollata Migh. 



L. columella Say. 



L. megasoma Say. Commonly cited from Lake Superior. 

 In the museum of the University of Michigan are specimens from 

 Drummond's Island at the head of Lake Huron. Its occurrence 

 within the state is thus definitely established. 



Limnsea reflexa Say. 



L. ,, var. zebra, Tryon. 



L. ., var. distortus Ross. 



L. ,, var. exilis Lea. 



L. desidiosa Say. 



L. emarginata Say. 



L. catascopium Say, 



L. caperata Say. Miles, Currier, Smith. 



L. pallida Ad. 



L. hum ills Say. 



L. lanceata Gld. Gould, Currier, Smith. 



L. intertexta Currier, MSS. Currier. 



L. contracta Currier, MSS. Currier. 



Physa Lord! Baird. Inhabits the northern part of the 

 state. Houghton Lake specimens were described as P. Parkeri 

 Currier. 



].(!., ii., Nov., 187y 



