HENRY J. FRANKLIN. 417 



Bonibus nevadensis Fletcher and Gibson, Can. Ent. Rec. (Ann. Rep't 



Ent. Soc. Ont.), 1907, p. 17. 

 Bombias nevadensis Swenk, Ent. News, XVIII, July, 1907, p. 295, 



n. 4. 

 Bombus " Cockerell, Can. Ent., XLII, 1910, p. 25. 



Davidson, Bull. So. Cal. Acad. Sci., X, 1911, p. 

 66. 



Types. — Queen from Nevada and in the collection of the 

 American Entomological Society ; male collected in Arizona 

 by Mr. Henshaw and possibly in the collection of the Mu- 

 seum of Comparative Zoology at Cambridge though I did not 

 see it there. The type specimens of iniprobus are in the 

 collection of the American Entomological Society. 



Pile rather short, fine and dejise. Dorsum of thorax yellow with 

 dark disc. Head of females black ; their pleura mostly black ; their 

 abdomen with the three first dorsal segments yellow and the rest black ; 

 their legs black and malar space medium. Males with face, occiput and 

 pleura yelloiv and apex of abdomen ferrugitwus . 



Queen. Head. — Symmetrical elongate trapeziform in outline as 

 viewed from in front. Face mostly black, but usually with ver}' faint 

 touches of yellov/ hair about the bases of the antennae ; occiput usu- 

 ally covered with mostly black pile, but with a more or less strong 

 admixture of yellow hairs ; sides of head, behind the eyes, black. 

 Labrum with tubercle-like areas very large, almost meeting at the 

 middle line and flat and coarsely and sparsely punctate at summit, 

 the translucent areas variable and often absent ; mandibles (fig. 30) 

 usually with no indication of a fourth tooth on the lower side of the 

 apical margin, usually rather protruding and rather sharply rounded 

 in that region ; malar space distinctly longer than its width at apex, 

 more than one-fourth as long as the eye ; ocelli as in auricomus ; fla- 

 gellum of antennae from one and two-thirds to two times as long as the 

 scape ; third antennal segment fully as long as the fourth and fifth 

 together, the fifth slightly longer than the fourth. 



Thorax. — Dorsum with disc naked, smooth and shining, this bare 

 area often having more or less black hair mixed with the yellow pile 

 surrounding it ; otherwise entirely covered with pale yellow pile of 

 greatly varying shade. Mesopleura with yellow pile extending down 

 onto them considerably below the level of the bases of the wings, but 

 their lower parts always covered with black pile to the bases of the 

 legs ; metapleura and sides of median segment always black. 



Abdomen. — Dorsum : segment one usually mostly covered with yel- 

 low pile, but sometimes with only a fringe of yellow on its hind border 

 and always with more or less black pile on the upper portion of its 

 front face, over (in front of) the apparent anterior margin, and the 



TRANS. AM. ENT. SOC, XXXVIII. (53) 



