284 The Ohio Journal of Science [Vol. XIX, No. 5, 



Subgenera and Groups of the Genus Formica Linn. 



1. First funicular joint about as long as the second and third taken together. 



Small, rather smooth, shining dark colored species 



Subgenus Proformica Rusky. 



First funicular joint shorter than the second and third taken together. ... 

 Subgen. Formica Linn. 2, 



2. Anterior edge of clypeus notched or emarginate in the middle.. sanguinea group. 

 Anterior edge of clypeus entire, rounded or subangularly produced in the 



middle 3. 



3. Sides of head subparallel, posterior border deeply and widely excised. ... 



exsecta group. 



Sides of head converging anteriorly, posterior border straight, convex or 

 feebly excised ; 4. 



4. Body robust. Head of largest individuals not or hardly longer than broad. 



Body opaque, color light or dark red with black gaster riifa group. 



Body more slender. Head of largest individuals longer than broad. Petiole 

 narrow, rather thick and with a blunt border. Color and sculpture 

 variable 5. 



5. Thorax rather short. Scapes distinctly curved at the base. Petiole flattened 



behind fusca group. 



Thorax longer. Scapes slender, very slightly curved at the base. Petiole 

 convex behind Subgen. Neoformica. 



Subgenus Proformica Rusky. 

 F. (P.) neogagates neogagates Emery. 



A small, smooth, dark or black shining species with light 

 reddish colored mandibles, antennas and legs. Sometimes the 

 cheeks and clypeus are light red in color. 



The workers of this species resemble the small workers of 

 F. suhpolita and for this reason the two species are sometimes 

 confused. F. Jteogagates differs from the former in its more 

 abundant, more finer and paler pilosity. 



The ants nest in small colonies under stones and are very 

 timid. They are a Sub-Boreal species and are not often found at 

 low elevations. 



F. sanguinea and its various subspecies make slaves of this 

 species. 



Subgenus Formica Linn. 



Sanguinea Group. 



1. Head long and narrow. Color of head, thorax and petiole brownish testaceous. 



Body opaque pergandei Emery. 



Head hardly longer than broad 2. 



2. Hairs nearly always absent on the dorsal portion of the thorax and petiolar 



border; short and sparse on the head and gaster. .sanguinea siibnuda Emery. 



Hairs present on the dorsal portion of the thorax and petiolar border; longer 



and more numerous on the head and gaster 3. 



3. Gaster black. Petiole with sharp superior border, which is usually notched 



in the middle sanguinea rubictmda Emery. 



Gaster brown. Petiole with blunt superior border, which is usually entire. 

 sanguinea suhintegra Emery. 



