1:2 THE CANADIAN ENTOMOLOGIST. 



Pass, both by Prof. Ciillette ; and July 31, Ridgeway (Ball). £, 

 Cimmaron, August 22 (Gillette). 



The type specimen was taken at " Pike's Peak, Col. Terr.," by Mr. 

 Winslow J. Howard. Prof. Cockerell records it from high altitudes in 

 New Mexico. Mr. Ashmead writes me that he has never seen a queen 

 of this species. It often is mixed with B. proximus in collections. 



/>'. terricola, Kby., 1837. 



This was determined for me by Mr. Ashmead ; I had not recognized 

 the species. $ , Ft. Collins (C. Stannard). 



B. Penmy Ivanicus, De Geer, 1775. 



B. americanoriun, Fabr. 



" Apathus elatus " in part. 

 I had the synonymy of this and the previous species mixed, but Mr. 

 Ashmead kindly straightened out the matter for me, and gives me the 

 above synonymy as correct, as far as Pennsy Ivanicus and Americanorum 

 are concerned. 



$ June 9, 23, 29; 9 July 23, August 8, 13; $ September 8, 17, 

 22 ; all at Ft. Collins. 



9 August 1, near Ft. Collins ; June 30, near Foothills ; July 8, 

 Livermore ; July 24, Vir. Dale ; ? August 4, Julesburg (3 by Ball) ? 

 August 7, 10, Rocky Ford. 



B. Titusi, n. sp., Ashmead (in litt.). 



A, . — Length, 16 mm. The abdomen dorsally covered with fulvous 

 pubescence. One specimen September 10, 1898, Lamar (Gillette). 



I hid this specimen under B. Peiui sylv aniens ; Mr. Ashmead 

 separated it out, and very kindly named it. The type is in the U. S. 

 Nat. Mus. 



A. ternarius, Say, 1838. 



? May 3, 4, 12, 14, 19, 27, 28, April 16, 23 ; $ July 4, 20, August 

 6 ; S August 5 ; all at Ft. Collins; 9 May 16, Bellvue ; $ July 8, 15, 

 Livermore; July 31, Ridgeway ; July 10, Lamar; July 27, September 3, 

 Vir. Dale ; July 20, Westlake ; August 3, Durango ; August 5, Antonito ; 

 c? Clear Ck. Can., July 18; July 7, Westlake; July 24, Vir. Dale; 

 August 3c, Ward ; August 24, Glenwood Sprgs.; October 8, Salida. 



This is the most common Colorado Bombus ; it has been recorded 

 heretofore from the State by Carpenter, " high Alpine," 1873; ^ r - Uhler, 

 Beaver Bk. Gulch, August 6; McCauley, "San Juan," 1877; J. D, 



