524 bulletin: museum of comparative zoology. 



Hairs less abundant than in the typical cinerea, absent on the sides 

 of the head and thorax; only a few long erect hairs on the gula. Legs 

 without erect or oblique hairs on their flexor surfaces. Pubescence 

 dense, but shorter and less silvery than in the typical cinerea. 



Color of body as in the darker forms of the European type; man- 

 dibles, cheeks, anterior border of clypeus, antennae, except the tips of 

 the funiculi, petiole, and legs dark red or brownish. 



Female. Length 7 mm. 



Closely resembling the worker in sculpture, pilosity, and color. 

 Hairs shorter and less abundant than in the female cinerea and as 

 in the worker absent on the sides of the head and thorax. Wings 

 colorless and more transparent than in the typical form, with pale 

 brown veins and darker stigma. 



Male. Length 7-8 mm. 



Differing from the male of the typical cinerea in the same characters 

 as the worker and female, the body being smoother, less pilose and 

 more delicately pubescent. There are very few erect hairs on the gula 

 and there are none on the legs. Gaster dark brown ; genitalia distinctly 

 infuscated. Antennae black, like the head, thorax, and petiole; 

 legs clear yellow. Mandibles very narrow, edentate, with long points, 

 black, with brownish tips. Wings as in the female. 



Described from many workers, two males, and a single rather im- 

 mature female from Florissant, Colorado (8,100 ft.). I have also found 

 this variety on Cheyenne Mountain, near Colorado Springs at about the 

 same elevation. At first sight it would seem to be a hybrid between F. 

 fusca var. argentea and the next variety, neocincrea, but the latter does 

 not occur at Florissant, being peculiar to lower altitudes, and the 

 var. altipetens is extremely common in the type locality, where it 

 forms populous colonies which inhabit large earthen mound-nests 

 (2-3 ft. in diameter and 6-10 inches high), overgrown with grass in 

 the alpine meadows. It also nests under stones in the same stations. 

 It is enslaved by Polyergus breviceps and the alpine forms of F. saii- 

 guinea. 



108. F. cinerea cinerea var. neocinerea Wheeler. 



F. cinerea Wheeler, Amer. nat., 1902, 36, p. 947. 



F. cinerea var. neocinerea Wheeler, Ants, 1910, p. 571. 



Worker. Length 3-6 mm. 



Shape of thorax varying froni that of the var. altipetens to that of 

 the typical cinerea. Petiole more as in the latter form, the border 

 being sharper and broader, but usually entire and sometimes bluntly 

 angular in the middle. 



