The Crustaceans of Lake Maxinkuckee. 229 
are so abundant during the summer and fall that they infest most of 
the rock bass, crappies, and bluegills. They seemed to be worst on the 
rock bass, nearly every one of which was bleeding in one or more places 
where these parasites had fastened in their skin. At this season these 
fishes are said to be “wormy” and are rejected by anglers and others 
who chance to catch them. 
The Isopods or Sowbugs are represented at the lake by two aquatic 
species, one in the lake proper, the other (Porcellio scaber) in the wood- 
land ponds and in damp places. The lake species is abundant all the 
year round among the Chara, especially in Outlet Bay. It is one of the 
most important fish foods, particularly of rock bass and bluegills. It 
sometimes forms the greater part of the food of those species. Little 
or nothing was learned of the habits of the pond species. There are, 
of course, several land species of these curious crustaceans. 
The Amphipods are represented by several species in the lake and 
the neighboring ponds. A large species (probably Gammarus pulex) 
was found near the shore, and a smaller form (probably Hyalella knick- 
erbockert) farther out in the lake among the aquatic plants. The Horse- 
tail (Ceratophyllum demersum) was one of its favorite haunts. Some 
of our herbarium specimens of this plant were found full of these beach 
fleas. Many specimens were obtained from the plants raked up from 
various depths. The Amphipods could be obtained by washing the plants 
in a tub or bucket of water. A few were taken at night in the towing- 
net. Some were found in stomachs of fishes seined August 3, 1906, 
south of Arlington station. 
The freshwater shrimp (Palxmonetes exilipes) was not common in 
or about the lake. Only a few were obtained, one on August 2, 1899, 
one on September 6, 1899, and one on October 23, 1900, all in the Outlet. 
Two were secured in Lost Lake, one on August 1, the other September 1, 
1900. Another was taken November 27, 1900, upon a mass of aquatic 
plants dredged some distance from shore in the lake. This species there- 
fore appears to be rather rare at this lake. In Little River near Aboite, 
Allen County, Indiana, immense numbers of this shrimp were found in 
masses of Ceratophyllum, from which the transparent creatures jumped 
with great alacrity when hauled up out of the water. They were found 
in great abundance also in Chester River near Chester, Md. 
