286 



Birge — Notes on Cladocera. 



Holopediidse . . 



Sididse 



Daphniidae. . . . 

 Macrothricidaa 

 Bosminidae . . . 



Lynceidae 



Polyphemidae . 

 Leptodoridae. . 

 Total 



I. 



II. 



1 











4 



1 







16 



4 



4 



8 



1 







4 











29 



7 



2 



1 











1 











64 



13 



6 



III. 



Besides these enumerated in the~table, one species, Ilyocryptus 

 longiremis, Sars, is common to Wisconsin and Australia. It is 

 possible that the forms described in the second section of this 

 paper under the names D. microcephala and D. longiremis, Sars, 

 are really entitled to rank as independent varieties. If so the 

 totals must be correspondingly altered. It is also to be ob- 

 served that Imhof has noted * but not described a new species 

 of Bosmina from G-reen lake, Wisconsin. 



The facies of our fauna is even more European than these fig- 

 ures would indicate. American varieties of European species 

 need, of course, no comment. They are only slightly dif- 

 ferent from the European form. The like may be said of 

 many of the Wisconsin forms considered as entitled to specific 

 rank. Many of them are very close to European species, as may 

 be seen from the following list: 



*Zoologischer Anzeiger, vol. xiv, p. 275. 



