wheeler: ants of the genus formica. 465 



Worker. Length 5-7 mm. 



Differing from the typical dakotensis in having the sides of the head 

 a httle less convex, the anterior border of head a little narrower, and 

 the gaster somewhat paler. The pubescence is lopger and more dis- 

 tinct on head and thorax. The pilosity is that of the type and not 

 that of the var. montigena. 



Female. Length 7-8 mm. 



Differing from the females of the typical dakotensis and the var. 

 montkjena in color, being yellowish red except the posterior borders 

 of the gastric segments, the antennae, and tibiae which are bro^\^^, 

 and the mandibles which are deep red. Wings with a yellowish tinge, 

 veins light brown, stigma darker. 



Male. Length 7.5-8 mm. 



Closely resembling the male of the var. moniigena, but the legs and 

 genitalia of a purer yellow and the gaster dark brown instead of black. 

 This is the case in ten specimens in my collection and can hardly be 

 due to immaturity. Wings colored as in the female. 



Host (Temporary). F.fusca var. subsericea. 



Type locality. — Wisconsin (Wasmann). 



Wisconsin: Prairie du Chi en (H. Muckermann). 



Emery described two different females under the name specularis^ 

 the first belonging to this variety, the second to the typical dakotensis. 

 Muckermann found several colonies of specidaris mixed with subsericea 

 and Wasmann concluded from tlais that the former ant was an incip- 

 ient slave-maker. It is evident that this conclusion is erroneous, 

 since my observations on the var. montigena, show that the species 

 is a temporary social parasite, like many, if not all, other forms of the 

 rufa group. 



Microgyna Group. 



53. F. microgyna microgyna Wheeler. 



F. microgyna Wheeler, Bull. Amer. mus. nat. hist., 1903, 19, p. 645, fig. 3, 

 S 9 cT, p. 656, fig. 1 (gynandromorph). 



Worker. Length 3.5-6 mm. 



Mandibles 8-toothed. Clypeus rounded in front, not produced, 

 carinate its entire length and with uneven surface. Maxillary palpi 

 rather long. .Head, excluding the mandibles, somewhat longer than 

 broad even in the largest workers, but little narrower in front than 

 behind, with straight posterior border and straight subparallel sides. 



