The Relation of Mollusks to Fish in Oneida Lake 275 
States. In the Saginaw Bay region it was noted on the 
under side of lily leaves. It is common in New York State, 
especially in ponds, ditches, swamps, and the quiet parts of 
lakes and rivers. Beauchamp lists it as from forest ponds in 
Onondaga County. (yrina has been observed on the Yellow 
Water Lily (Vymphea advena). 
The genus Physa is in a chaotic state as regards the 
specific distinctness of a large number of its species. 
Authors following Binney have classed almost all species 
under the all-embracing name of heterostropha and it is 
therefore impossible to compare the distribution of any 
Physa under this name. The three forms listed above are 
quite distinct and need never be confounded. 
Famity ANCYLID#, 
Genus Ancytus Geoffroy. 
45. Ancylus tardus Say. Fig. 45, No. 18. 
This small fresh-water limpet was observed only in Seriba 
Creek on stones in shallow, rapidly flowing water. It is 
widely distributed in the eastern and central parts of the 
United States and in Canada. It is common in New York 
State. Beauchamp lists it from Onondaga County on stones 
in rivers. 
46. Ancylus fuscus Adams. Fig. 45, No. 16. 
Observed at two stations, both sheltered habitats, and one 
a Typha marsh. Its habit of clinging to vegetation espe- 
cially dead Typha leaves, is noteworthy. It is as widely dis- 
tributed as is tardus. Recorded by Lewis from western New 
York but not included in Beauchamp’s list of Onondaga 
County. It has been collected from dead leaves of Cat-tail 
(Typha angustifolia) wpon which it feeds. 
Fig. 46. 1, 5, Vivipara contectoides; 2-4, Campeloma integrum, 6-8, 
Campeloma decisum; 9-12, Lymnaea stagnalis lillianw ; 13- 
16, Planorbis trivolvis; 17-18, Planorbis binneyi; 19-20, 
Planorbis trivolvis, var. 
> 
