HENRY J. FRANKLIN. 269 



Dimensions. — Length : queen, 15 mm. to 18 mm. ; worker, 9^ mm. 

 to 15 mm. ; male, \1\ mm. to 15^ mm. Spread of wings ; queen, 37 

 mm. to 39 mm. ; worker, 23 mm. to 34 mm. ; male, 28 mm. to 34 mm. 

 Width of abdomen at second segment: queen, 9 mm. to 10 mm. ; 

 worker, S\ mm. to 8^ mm. ; male, 6J mm. to 7 mm. 



Redescribed from several queens (from Oregon and Idaho) , 

 from numerous workers (from Washington, Oregon and Mon- 

 tana) and from several males (from Idaho, Montana and New 

 Mexico — one of them a cotype oi perixanthus CklL). 



I have here designated both the queens and workers, above 

 described, as typical, on the basis of the coloration of the type 

 queen, so that the color variations of both may be conveni- 

 ently described together. 



Variation. — This is one of our most variable species. I 

 here describe such forms as seem marked distinctly enough 

 to deserve description. Between these various forms, I have 

 seen almost every conceivable gradation both in the males 

 and in the females. I have also examined the genitalia of 

 the males of the different color variants and of the two sub- 

 species and I have found them all alike. There is one varia- 

 tion, belonging to this species, which seems to be distinctly 

 marked enough (characters and habitat both considered) to 

 be given the rank of subspecies. This variation does not 

 seem to have been recognized by previous workers on the 

 group. It is pretty generally distributed throughout the 

 Pacific States and western Canada, though apparently a rare 

 form everywhere, except in California, where, at least in por- 

 tions of the state, it is very abundant. To this form I here 

 give the name nigroscutatus. The two subspecies, with their 

 respective color variants, are as follows : 



Subspecies occidentalis. — The typical form above described; 

 its color variants are : 



Color Variant 1. — Queen and worker like the typical form, but with 

 the fourth dorsal abdominal segment largely, and sometimes entirely, 

 covered with white pile. Many specimens, from British Columbia, 

 Washington, Montana, Utah, Oregon and Northern California (the B. 

 occidentalis of Cresson) . 



Color Variant 2. — Queen and worker like Color Variant 1, but with 

 more or less yellow pile on the third dorsal abdominal segment and 



TRANS. AM. ENT. SOC, XXX VIII. 



