508 bulletin: museum of comparative zoology. 



peus, and mandibles dark brown. Thorax, petiole, legs, scapes, and 

 base of funiculi clear yellowish red, the legs a little paler; only in small 

 workers is there a slight tendency to infuscation of the thoracic dorsum. 

 Gaster black or dark reddish brown, venter and base of first segment 

 often paler. Petiole as in neorufibarbis. 



Female (dealated). Length 7 mm. 



Very closely resembling the female of gelida, especially the form 

 with pale thorax, having the mesonotum ornamented with three large 

 dark brown or black blotches, but the pubescence, especially on the 

 gaster, is finer and denser. Frontal area shining. 



Type locality. — South Dakota: Hill City (Th. Pergande). 



South Dakota: Harding County (S. S. Visher). 



Utah: Willow Canyon, Salt Lake County, (R. V. Chamberlin). 



Montana: Helena, Elkhorn, Nigger Hill, Powell County (W. M. 

 Mann). 



Idaho: Moscow (J. M. Aldrich). 



Oregon: Portland (Amer. Mus. Nat. Hist. Coll.). 



Washington: San Juan Lsland (W. M. Mann); North Bend (T. 

 Kincaid); Union City (J. C. Bradley). 



British Columbia: Alert Bay, Vancouver Island (H. I. Smith); 

 Chillimack Valley (J. M. MaCoun); Carbonate, Fielde (J. C. Bradley). 



Alberta: Lake Minnewonka (J. C. Bradley). 



This variety, of which I have seen many workers, but only one 

 female, is very closely related to the var. gelida though evidently 

 occurring at much lower altitudes. Superficially it resembles the 

 European F. rufibarbis but can be at once distinguished by its shining 

 and much less pubescent gaster, smooth frontal area, and much sparser 

 pilosity. 



I believe that I am right in limiting Emery's name neorufibarbis to 

 this form, first, because he describes the color as like that of the 

 European rufibarbis and second, because he cites South Dakota and Ne- 

 braska among the list of localities. The form I have called gelida 

 cannot occur in these states. Third, I possess two workers from South 

 Dakota sent me several years ago by Pergande under the name " 7ieo- 

 rufibarbis." These evidently belonged to the cotype series. If Emery 

 actually included both forms under the latter name, it should be 

 applied to the specimens from South Dakota, the first locality men- 

 tioned, and not to the specimens from Colorado, Montana, and Cali- 

 fornia, which in part at least were probably referable to gelida. 



