List of Crustacea Cladocera from Madison , Wis. 
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LIST OF CRUSTACEA CLADOCERA FROM MADISON, 
WISCONSIN. 
By E. A. BIRGE, 
Professor of Zoology, University ofWisconsin. 
In 1878 the writer published Notes on Cladocera in the fourth volume 
of the Transactions of this Academy,* in which were noted twenty-five 
species of Cladocera found at Madison. Returning to the subject with 
better means of collecting and a much larger command of the literature 
of the group, I have been able to enlarge greatly the number of species 
and to identify them more accurately. As the task of reviewing the 
greatly scattered literature, especially of the Lynceidce , seems likely to 
occupy some time, it seems advisable to print a list of the species 
already found, with notes on rare or new forms. 
A glance at the subjoined list of sixty-four species and varieties 
regarded by many European writers as species, will show how close our 
fauna is to that of Europe. Out of the whole number, only nine are 
peculiar to this country and of these five are varieties of species found 
elsewhere, or are very close to foreign species. Three species are deter¬ 
mined as new, Latonopsis occidentcilis from the Sididce , Moina sp. nov. 
from the Daphnidce , Alona lepida from the Lynceidce. 
With the exception of five species and varieties ( Daphnia pidex , Zb 
retrocurva , Alona tenuicaudis , and the species of Moina), all of the 
species in the list have been found in Lake Wingra. This is a small lake 
about one and three-fourths miles long and half as wide, with broad 
margins of marsh all around it. In the marsh the water is from a few 
inches to two feet deep between the areas of wild rice and reeds, and the 
bottom is partly composed of vegetable debris and partly covered by a 
dense growth of Chara. The lake itself hardly exceeds fifteen feet in 
depth, and almost the entire bottom is overgrown with water plants 
of various kinds. Among these weeds and in the marshes Cladocera 
abound. The abundance of food and variety of locality offered proba¬ 
bly account for the great number of species. In Lake Mendota, a 
much larger body of water, six miles by four, and having a depth 
of sixty to eighty feet, I have found only thirty-eight species of Clado- 
* Vol. IV, 1876-7 (printed 1878), pp. 77-110. PI. I, II. 
