wheeler: ants of the genus formica. 393 



31. Erect hairs sparse on upper surface of head, thorax, and petiole. 



tnmcicola integroidcs Emery. 

 Erect hairs on upper surface of head, thorax, and petiole dense 

 and abundant. 



truncicola integroides var. coloradensis, var. no v. 



Females. 



1 . Palaearctic forms 2 



Nearctic forms 5 



2. Frontal area opaque; antennal scapes short and stout. 



uralensis Ruzsky. 

 Frontal area shining; antennal scapes longer and more slender . . 3 



3. Gaster very smooth and shining, scarcely pubescent . . rufa Linne. 

 Gaster opaque or subopaque, distinctly pubescent 4 



4. Gaster opaque, densely pubescent, brownish black, except the ex- 



treme base and tip, which are reddish. . . . rufa -pratcnsis Retzius. 



Gaster subopaque, brown vAth. red base, or red with fuscous 



posterior margins to the segments truncicola Nylander. 



5. Antennal scapes with numerous erect or suberect hairs 6 



Antennal scapes without erect hairs, or with only a few on the 



posterior surfaces 7 



6. Hairs on scapes and legs oblique or suberect .... orcas Wheeler. 

 Hairs on scapes and legs more erect; on the body coarser and 



more abundant oreas var. comptula, var. nov. 



7. Gaster invested with very long, appressed hairs 8 



Gaster not invested ■u'ith such hairs 10 



8. Gaster yellowish red like the head and thorax, its long, appressed 



hairs hooked or curved at their tips 9 



Gaster blackish browTi, except the base and anal region; its 

 long, appressed hairs not curved at their tips. . . comata Wheeler. 



9. Petiolar border with a fringe of very long hairs. . . . ciliata Mayr. 

 Petiolar border without a fringe of long hairs. 



criniventris Wheeler. 



10. Head and thorax very smooth and shining, petiole with trans- 



versely truncated superior border 11 



Head and thorax opaque or subopaque, petiole not truncated 

 above 13 



11. Gaster brown 12 



Gaster red with brown posterior borders to the segments. 



dakotensis var. specularis Emery. 



