The Crustaceans of Lake Maxinkuckee. Leva | 
(2) the Parasitic Copepods; (3) the Amphipods or Beach Fleas; (4) the 
Isopods or Sowbugs; and (5) the Crawfishes. 
THE PLANKTON SPECIES. 
The list of species contained in the Plankton collections of 1899 and 
1900, and a discussion of their abundance, distribution and habits, will 
be found in Professor Juday’s report. A few additional species were 
later obtained in the small ponds about the lake. 
Of the individual species not much can be said; our studies were too 
general for that purpose. It may be stated, however, that plankton 
species of crustaceans constitute a large part, probably nearly all, of 
the first food of the young of many fishes, and much of the food of 
some species of fishes throughout their entire lives. The little Stickle- 
back (Eucalia inconstans), for example, may be mentioned as one of 
such species. Examples of this species kept in an aquarium fed eagerly 
on any and all plankton crustaceans which we placed in the aquarium 
with them. We observed also that these small crustaceans are captured 
and eaten freely by those curious carnivorous plants, the bladderworts. 
Of the whole group it can be said that they are present throughout 
the year in greater or less abundance. The abundance varies greatly, 
however, from time to time, as shown by Juday. On September 6, 
1906, peculiar ripples were observed on the surface of the otherwise 
smooth lake. Upon cautiously approaching the spot it was found that 
the disturbance was caused by large schools of young black bass, circling 
about and feeding voraciously. Upon drawing a towing-net through the 
place great quantities of several species of plankton crustaceans were 
obtained. 
On many occasions the lake surface in large areas was seen to be 
covered with a thin scum which, on examination, was found to consist 
chiefly of the cast-off skins of minute crustaceans. 
On November 5, 1906, Entomostraca were present in such remark- 
able abundance at and near the surface of the lake that the water had 
the appearance and consistency of thick soup, the little animals actually 
crowding each other in the water. The next day great windrows of these 
crustaceans were found washed up on the shore at Long Point. Two 
days later they were again observed forming dense clouds at and near 
the surface of the lake off the Norris boathouse. A 4-drachm vial was 
simply dipped into the water and about 100 of the creatures were 
secured. 
A quantity of plankton collected July 7, 1909, and examined quali- 
tatively by Professor A. A. Doolittle of the department of biology, 
Washington, D.C., high schools, gave the following results: 
