wheeler: ants of the genus formica. 457 



46. F. CRiNiVENTRis Wheeler. 



F. crinita Wheeler, Journ. N. Y. ent. soc, 1909, 17, p. 87, U 9 . 

 F. criniventris, nom. nov. Wheeler, Psyche, 1912, 19, p. 90. 



Worker. Length 4-6.5 mm. 



ResembHng the worker of the preceding species but averaging some- 

 what smaller. Head, excluding the mandibles, a little longer than 

 broad, even in the largest workers; narrower in front than behind 

 with nearly straight posterior and lateral margins. Eyes rather large. 

 Mandibles 7-8 toothed. Clypeus carinate, with entire anterior border, 

 slightly projecting in the middle. Frontal furrow distinct. Antennae, 

 thorax, and petiole as in comata. Palpi rather short. Gaster and legs 

 of the usual shape. 



Body subopaque, very finely shagreened; bases of mandibles, 

 frontal area, and corners of clypeus glabrous. Mandibles and clypeus 

 finely, longitudinally striated. 



Hairs yellow; absent on the head, thorax, petiole, and appendages, 

 blunt and scattered on the gaster, pointed on the clypeus, mandibles, 

 and venter. Pubescence yellowish and very short, inconspicuous 

 on the head, thorax, and petiole, somewhat longer on the legs and 

 gaster; on the latter rather dense and nearly concealing the surface. 

 Eyes hairless. 



Yellowish red; gaster dark reddish brown, except the anal region 

 and a spot at the base of the first segment, which are yellowish; tips 

 of antennal funiculi, middle portions of femora and tibiae brownish 

 or reddish. The smallest workers have the upper surface of the thorax, 

 especially the pro- and mesonotum, somewhat infuscated. Mandibu- 

 lar teeth black. 



Female. Length 6.5-7 mm. 



Resembling the female of ciliata. Body shining throughout, very 

 finely shagreened, without pubescence. Hairs very long, yellow, 

 curled or hooked at their tips, confined to the clypeus, gaster, and ven- 

 tral surface of the petiole; on the gaster appressed and arranged in 

 two rows near the posterior border of each segment. Body and appen- 

 dages yellow; teeth of mandibles and anterior edge of clypeus black; 

 scutellum, metanotum, and anteromedian and two parapsidal blotches 

 on the mesonotum, anterior borders of cheeks, and a narrow band 

 parallel with the posterior edge of each gastric segment, brown. An- 

 tennal funiculi infuscated towards their tips. Wings grayish hyaline, 

 with pale brown veins and darker brown stigma. 



Host. Unknown, probably F. fusca var. argentea or neoclara. 

 Type locality. — Colorado: Boulder, (Wheeler). 

 Montana: Helena (Hubbard and Schwarz). 



