126 Illinois State Laboratory of Natwal History. 



hair as long as the ramus itself. The inner ramus of this 

 leg is very long, reaching beyond the middle of the terminal 

 joint of the outer ramus. It is slightly concave towards this 

 ramus and terminates with a broadly rounded or subtruncate, 

 thickly ciliate end, forming an acute outer angle and an 

 obtuse inner one. Seen at right angles to this view, the tip 

 is simply obtusely pointed. 



" The right leg of the male is without remarkable distin- 

 guishing characters. Basal joint of the outer ramus about 

 two thirds as long as the peduncle and nearly as wide; sec- 

 ond joint slightly longer than the peduncle, equal to the first in 

 width ; and the terminal claw sinuate or irregularly curved. 

 The stout seta on the outer margin of the second segment of 

 this ramus is borne at about a quarter the length of the seg- 

 ment from the distal end, and is approximately half as long 

 as the segment to which it is attached. The inner ramus is 

 a little longer than the basal joint of the outer. It is not 

 dilated or otherwise modified, but terminates bluntly, bearing 

 at the tip a covering of long cilia, 



"The right antenna of the male is without notable dis- 

 tinctive characters. The antepenultimate segment is as long 

 as the two following taken together ; the fourth from the tip 

 bears two long sword-like spines at its margin, both attached 

 to its basal fourth ; the expanded segments are well armed 

 with conical spines, straight and curved, but without hooks. 



" Small lakelet near Gardiner, Montana."* 



This is the only one of the four species described by Dr. 

 Forbes ('93) which I have found in any other collections than 

 the original ones. In collections loaned me by Prof. L. S. 

 Eoss, of Drake University, Iowa, made by him at Portage 

 Slough, Manitoba, Canada, in June, 1895, I found quite a 

 number of specimens of this species, which, however, exhibit 

 a number of peculiarities. The fifth pair of legs in the 

 female are stouter and the inner ramus is relatively shorter 

 than in the Montana specimens, the latter not reaching to 

 the end of the first segment of the outer ramus as it does in the 

 type. The spines on the inner ramus also have a more 



♦Description quoted from Forbes, '93 



