The Relation of Mollusks to Fish in Oneida Lake 309 
Famity Parnipa (Water-penny Beetles). 
Psephenus lecontei Lee. 
The larva of this beetle lives on stones in running water 
and on exposed shores subject to violent wave action. It 
was very abundant at stations XVI, XXX, habitat 2, and 
station X X XITI. 
SUMMARY. 
The study of the biota associated with the Mollusea indi- 
sates that the various groups represented are fully as well 
developed as is the Mullusea. Comparisons of groups can- 
not be made at this time as in the majority of cases only such 
species were collected as were observed while collecting 
mollusks. The number of leeches (10) and eaddis-flies (10) 
is noteworthy, indicating an unusually large development of 
these groups. The use of Entomostraca as well as the larve 
of flies and May-fly and dragon-fly nymphs in large numbers 
by fishes as food indicates a great abundance of these 
animals. Seventy-seven aquatic species are recorded, but 
this number will without doubt be very largely increased 
when systematic search is made. <A rich harvest of inverte- 
brate life awaits the student who can give the time necessary 
for its collection and study. 
