The Relation of Mollusks to Fish in Oneida Lake 269 
Whitefish, Common Sucker, Pumpkinseed, Manitou Darter 
and Tessellated Darter. 
38. Ammnicola lustrica Pilsbry, variety. Fig. 45, No. 21. 
A single very narrow Amnicola (field No. 217) was found 
among debris at station X X XI, habitat 2, C, associated with 
typical. lustrica. It greatly resembles Paludestrina nick- 
liniana in general form, and is an example of the statement 
expressed under the last species. Should more of this nar- 
row form be collected it would need to be differentiated as 
a separate species. 
Famity PLevuROCERIDA, 
Genus GontoBasis Lea. 
39. (Gonobasis livescens (Menke). Fig. 47, Nos. 9-12. 
Observed at fifteen stations where it lives on bouldery 
points in one to three feet of water, usually exposed to the 
full force of the waves. Young individuals, a few milli- 
meters in length, have been noted on a sandy bottom. The 
young are strongly carinated on the whorls. This char- 
acteristic snail is distributed from New York to Lake Michi- 
gan and southward to Illinois. It is recorded from Lake 
Michigan and the Traverse Bay region, the Saginaw Bay 
region, where it lives on unprotected, rocky, shallow shores, 
and the Georgian Bay region where it occurs in similar 
habitats. It is very abundant in New York State and is 
listed by Beauchamp from Onondaga County. It has been 
observed to feed upon green filamentous alge, and is said to 
eat dismids and diatoms. 
Famity VALVATID&. 
Genus Vatvata QO. F. Miller. 
40. _ Valvata tricarinata (Say). Fig. 45, Nos. 10-12. 
Observed only at station XX XI, habitat, 1, C, where it 
occurred on a sandy bottom. It has been noted in alge 
