THE CANADIAN ENTOMOLOGIST. 43 



Putnam, from Empire, 1876; Prof. Cockerell, from Willow Ck. } Custer 

 Co., August 22 ; and by Dr. Rothrock, in 1872, from "Colorado"; and 

 others. 



B. rufocinctus, Cress., 1863. 



9 Tune 16, Ft. Collins; # August 16, Horsetooth Gulch; both 

 determined by Ashmead. Prof. Cockerell records this species from 

 Custer Co., May 28, and August 19. 



B. bifarius, Cress., 1878. 



9 May 28; $ August 26 (Burner), at Ft. Collins; 9 May 23, 

 Boulder; 9 9 July 7. Westlake ; July 1, Rist Canon; 9 August 23, 

 Marshall Pass (Gillette); August 25, Alder; July 10, Lamar; 9 ^ 

 August 22, Cimmaron ; August 30, Ward ; August 2, Muldoon (Ball) ; 

 £ July 23, Palmer Lake; July 3r, Ridgeway ; August 14, Steamboat 

 Springs. 



B. sylvicola, Kirby, 1837. 



9 August 1, Lizard Head (Ball); 9 August 25, Alder (Gillette) ; 

 August 2, Muldoon; J 9 August 27, Marshall Pass; 3 9 '$ I0 ^ August 

 30, Ward (Ball). All determined by Ashmead. Prof. Cockerell records 

 it from Ula, Custer Co., July 30. It is certainly a distinct high Alpine 

 species, and I had not recognized it. 



B. juxtus, Cress., 1878. 



9 July 8, Livermore ; 9 July 20, Ft. Collins ; July 23, Vir. Dale ; 

 August 2, Estes Park (Gillette); August 20, North Park (Ball); ^ 

 August 22, Palmer Lake. 



I have seen a male from Woods Holl, Mass. (Gillette), that belongs 

 to this species. 

 B. flavifrons, Cress., 1863. 



9 9 August 27, Marshall Pass; % 9 S > August 1, Lizard Head 

 (Ball); August 30, Ward. 



This species in general appearance sometimes resembles B. juxtus 

 but can be readily separated. Some specimens from Lizard Head are 

 very bright, and the thorax has much more black anteriorly than in 

 ordinary specimens. 



B. Couperi, Cress., 1878. 



9 $ August 30, Ward; August 1, Lizard Head, all determined by 

 Ashmead. Prof. Cockerell has stated that he did not feel warranted in 

 separating Couperi and Putnami from frigidus after examining the types 



