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 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. “ l£< 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 Richard (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. 
