wheeler: ants of the genus formica. 437 



most of the older authorities, as will be seen by consulting the synon- 

 ymy, and Emery himself says: " F. rufa truncicola diirfte eher als 

 besondere Art betrachtet werden." The difference is more apparent 

 in the habits, perhaps, than in structure, for truncicola does not build 

 large independent mound-nests like F. rufa, pratensis, aggcrans, 

 obscuripcs and their varieties, but nests about stumps and logs or the 

 roots of plants, though it banks these with vegetable detritus. The 

 same habit holds of the forms which I regard as American subspecies 

 and varieties of truncicola. 



Like rufa, the F. truncicola queen establishes her colony by tempo- 

 rary parasitism on F. fusca, as Wasmann has shown. 



32. F. TRUNCICOLA TRUNCICOLA var. YESSENSis Forel. 



F. rufa race truncicola var. yessensis Forel, Mitth. Naturh. mus. Hamburg, 



1901, 18, p. 66, y . 

 F. rufa truncicola var. yessensis Ruzsky, Formicar. Imper. Ross. 1905, p. 335; 



Emery, Deutsch. ent. zeitschr., 1909, p. 188. 



Worker. Differing from the typical truncicola in having the basal 

 surface of the epinotum somewhat shorter and more convex and in 

 the sparser, shorter pilosity. There are very few hairs on the antennal 

 scapes and none on the extensor surfaces of the tibiae. The flexor 

 surfaces bear the usual series of oblique bristles. 



Japan: Serachi, Province Ishikari, Island of Yesso. 

 Siberia : Tomsk and Tobolsk, according to Ruzsky. 



33. F. TRUNCICOLA TRUNCICOLA var. SINENSIS, var. nov. 



Worker. Length 4-8 mm. 



Opaque; mandibles and clypeus slightly shining, delicately longi- 

 tudinally striate; frontal area and frontal groove very smooth and 

 shining. 



Erect hairs golden yellow, less abundant than in the typical trunci- 

 cola, absent on the upper surface of the head and clj'peus, middorsal 

 region of the pro- and mesonotum and flexor surfaces of the tibiae, 

 long on the gula, epinotum, fore coxae, and gaster. Eyes hairless. 

 Pubescence fine and rather sparse, most easily visible on the epino- 

 tum and on the gaster where it is sufficiently abundant to produce a 

 grayish tinge, extremely fine on the antennae, head, pro- and mesono- 

 tum. 



Head, thorax, petiole, and legs deep, dull red; mandibles and front 

 of head a little darker; cheeks and clypeus a little paler; smallest 



