Order, Isopoda. 
Oniscidz. 
Porcellio rathkei Brandt. 
Asellidee. 
Asellus tomalensis Harford. 
The economic importance of the smaller crustacea is well known 
They form one of the most important food supply links between the lower 
plants and animals on the one side and the higher animals on the other. 
A small minnow about one inch long was kept for some time and fed on 
Amphipoda (Hyalella knickerbockeri). A small darter hatched from the 
egg and cared for by Mr. W. I. Lower was fed on Entomostraca, principally 
Ostracoda, until it was eighty-seven days old and was about three-eighths 
of an inch long. 
As parasites the small crustacea frequently cause great mortality 
among fishes, but so far only one parasitic form has been found in Winona 
Lake and that in extremely small numbers on the gills of the Black Bass 
(Micropterus salmoides). Examination of other fish and of the clams in 
the Jake failed to reveal other parasitic crustacea. 
Three species of crayfish were found. Cambarus propinquus was 
abundant in the streams flowing into the lake and also in the outlet, but 
was extremely scarce in the lake. Cambarus diogenes and Cambarus im- 
munis were found only in burrows along the shore and along the edge of 
the streams and in the adjacent low ground. The burrows are from two 
to three feet deep and contain six to eight inches of water at the bottom. 
Where the soil is homogeneous they extend obliquely downward in almost 
a direct course, but in the presence of stones and other obstructions they 
wind about sometimes to a considerable extent. In digging the holes the 
crayfish work head downward and bring the earth up between the chele 
and the first pair of walking feet and deposit it by the aid of the second 
pair of walking feet. Attempts were made to get the burrowers out of 
their holes by pouring strong salt solution and also formalin into them. 
Sut the crayfish would die before they would come to the surface. ‘Traps 
at the surface were also resorted to without success and the only practical 
method of obtaining them was by means of a ditching spade which re- 
quired no small amount of labor. 
While the crayfish were always found in shallow water, under and 
among stones and sticks or in burrows, it was found that they could live 
