248 THE CANADIAN ENTOMOLOGIST 



aa. Wings with clouded areas. 



c. Venter with brown markings. 



d. The hind wing wholly clouded with 

 brown or almost so. Fore wing 

 clear S. minis 



dd. A small brownish cloud along the axillar 

 fold of fore wing. Hind wing 

 clear S. typicus 



cc. Venter transparent whitish S. femoralus. 



Nymphs. 

 a. Setae dark-banded beyond middle. 



b. Setae dark-banded just beyond middle and again across 



the tips 5,. alfernafus. 



bb. Setae but once banded. 



c. Venter with U-shaped dark areas; spines of the 

 9th abdominal segment just half the length of 

 tergum of 10th segment in the median 



line S. occidentalis. 



cc. Venter with large dark triangular areas; spines of 

 9th abdominal segment slightly o\'er half the 

 length of tergum of the 10th segment in the 



median line 5. triangularis. 



aa. SetcX unhanded S.'mirus 



Siphlonurus alternatus Say. 



For description of. adult see Eaton's Revisional Monograph, 

 p 219, and of nymph, Bull. 47, N. Y. State Mus., 1901. 



The nymph shows the same ventral abdominal markings as 

 the adult. See PI. IX, fig. 8. 



Siphlonurus occidentalis Eaton. 



The nymphs and adults of this species w^ere taken by Professor 

 T. D. A. Cockerell at Florissant, Colorado, June 30, 1907, at a 

 place where subimagos were emerging in numbers. Other speci- 

 mens were taken by Prof. Cockerell at Twin Lakes, Col.. Upi^er 

 Lake, July 14, 1902. See PI. IX, fig. 9. 



Nymph. — Length 13 mm.; leg 4.5 mm.; setae 5 mm. 



