Limnocalanus. 201 



I have found E. lacustris in only two localities beside the 

 Great Lakes — in Green Lake and Lake- Puckaway. Probably, 

 however, it is abundant in other localities, as Forbes reports it 

 from many lakes in Illinois, Michigan, and southern Wis r sin. 



The peculiar form of the male abdomen distinguishes nis in 

 a striking manner from all other copepods. 



Genus LIMNOCALANUS Sars. 



Limnocalanus macrurus Sars. 

 Plate IV. Fig. 7. 



1863. L. macrurus Sars (11) pp. 228-229. 



1882. " " Forbes (22) p. 648. 



1886. Centropages grimaldi DeGuerne (29) pp. 1-10. 



1888. L. macrurus Nordqvist (31) pp. 31-37, pi. I, figs. 9-11; 



pi. II figs. 1-5; pi. Ill figs. 1-4. 



1889. L. macrurus DeGuerne and Eichard (32) p. 77, pi. IV, 



figs. 5, 11 and 12. 

 1891. L. macrurus var. auctus Forbes (35) p. 706. 



L. macrurus is abundant in Green Lake. It is a species of 

 especial interest because of its wide distribution. It is found 

 quite generally throughout northern Europe. Forbes has found 

 it in Lake Michigan, Lake Superior and Lake Geneva. I have 

 found it also in collections from Lake Huron, Lake St. Clair, 

 and the St. Clair river. 



