INVERTEBRATES 



Cambarus diogenes Girard Detroit and Lake Erie.* 

 " fodiens (Cottle). (Faxon). 

 " affinis (Say) Niagara.* 



propinquus Girard. (Faxon). 



virilis Hagen. (Faxon). 



immunis Hagen Detroit* 



rusticus Girard Lake Erie.* 



The following shrimp, received through Dr. 

 E. M. Walker, has been found in the Welland River 

 and may occur here, 



Palaemonetes exilipes Stimpson.* 



Schizopoda. 



The deep-water shrimp of the Great Lakes, which 

 forms such a considerable part of the food of the 

 whitefish, is also found in the lakes of Northern 

 Europe. It has doubtless been derived independently 

 on the two continents from the marine Mysis oculata. 



Mysis relicta Loven. Stomach of ling, Port Credit 

 (obtained by Mr. A. R. Cooper). 



Amphipoda. 



The small shrimps of this group often swarm 

 along the quiet margins of the lakes, the streams and 

 the ponds and also on the bottom down to consider- 

 able depths. They serve as food for many of the 



itoporeia hoyi Smith (by Nicholson as P. affinis). 

 18 273 



