MOUNTAIN ANTS OF NORTH AMERICA. 551 



Canada: Saskatchewan (Frcy 1909), five workers and six females." 

 As I have not seen this variety, I quote Santschi's description 

 (Ann. Soc. Ent. Belg. 57, 1913, p. 435). In certain particulars it 

 seems to resemble the form described below as F. hcwitti, but I cannot 

 suppose that Santschi would have described this form as a variety of 

 cinerea. 



160. Formica cinerea var. lepida Wheeler. 

 Lower California: La Ensenada (F. X. Williams). 



California: Lemon Cove, Tulare Co. and Blue Lake, Humboldt Co. 

 (J. C. Bradley). 



Washington: Seattle (T. Kincaid and Wheeler). 



I found workers of this variety running on the sidewalks in Seattle. 

 Two dealated females taken in the same city by Kincaid measure 

 nearly 9 mm. They are colored like the workers, with the sutures 

 and parapsidal furrows of the thorax blackish. 



161. Formica cinerea subsp. pilicornis Emery. 

 California: Jacumba (J. C. Bradley). 



Recorded only from numerous localities in the Coast Range of 

 California, from San Francisco to San Diego. 



162. Formica sihyJla Wheeler. 



California: Yosemite Valley, from Yosemite Village, 4000 ft., to 

 Glacier Point, 8000 ft., and Tallac, Fallen Leaf Lake and the Moraine 

 east of Angora Peak, near Lake Tahoe (Wheeler). 



The types of this interesting species were, taken by Prof. C. F. 

 Baker in King's Canyon, Ormsby County, Nevada, on the eastern 

 shore of Lake Tahoe. In the Californian localities above cited I saw 

 numerous colonies, each comprising a rather small number of workers 

 and nesting in craters 6 to 8 inches in diameter in sandy soil fully 

 exposed to the sun. The workers, which run very rapidly, were seen 

 outside the nests only during the early morning and late afternoon 

 hours of the hot days of July and August. I failed to secure the 

 hitherto unknown female. In life the worker has a peculiar bronzy 

 appearance owing to the dense and rather long grayish yellow pubes- 

 cence covering the whole body. It is readily distinguished from the 

 forms oifusca by the numerous long, erect hairs on the gula, and from 

 the forms of cinerea by the absence of erect hairs on the thorax and 

 petiole, their sparse development on the head and gaster, the less 

 angular epinotum, more slender antennae and less curved scapes. 



