522 bulletin: museum of comparative zoology. 



Male. Length 8-10 mm. 



Body slender, as in the typical fusca. Mandibles bidentate or 

 edentate. Head shaped like that of the male of fusca. 'Petiole low 

 and thick, with blunt superior border, which is transverse and feebly 

 and broadly excised. 



Body, including the frontal area, opaque, gaster slightly glossy. 



Hairs grayish, erect, short, abundant, except on the upper surface 

 of the gaster, oblique on the legs. Pubescence brownish, dense but 

 shorter than in the worker so that the body is less silvery. 



Black; gaster dark brown, genitalia and legs yellow; the middle 

 portions of the femora and the genital appendages sometimes infus- 

 cated, scapes and mandibles often reddish or yellowish. 



Central and Southern Europe and Asia Minor (Caucasus Moun- 

 tains). 



This species nearly always nests in pure sand or sandy soil, prefer- 

 ring river and lake bottoms. It forms huge colonies often extending 

 over many nests, the entrances of which are not surmounted by 

 mounds but only by small, obscure craters. The color of the worker 

 and female is variable, being sometimes as dark as the typical fusca, 

 in other colonies more like rvfibarbis. Specimens of the former 

 coloration were called fusco-cinerea by Forel, of the latter cinereo-rufi- 

 barbis. It is doubtful, however, whether these represent transitions 

 to fusca and rufibarbis. They may be hybrid forms. 



104. F. cinerea cinerea var. fusco-cinerea Forel. 



F . fusco-cinerea Forel, Denkschr. Schweiz. gesell. naturw., 1874, 26, p. 55, 57, 



58, ^ 9 &. 

 F. cinerea w&v. fusco-cinerea Dalla Torre, Catalog. Hymen., 1893, 7, p. 194. 



Worker and Female. Intermediate in pilosity and pubescence 

 and also in habits between F. fusca and cinerea. 



Male. Apparently indistinguishable from the male of the typical 

 cinerea. 



Zurich and Canton Vaud, Switzerland. Emery does not recognize 

 this form in his revision of the Palaearctic Forniicae. It is probably 

 very closely related to the form described below as var. altipetens 

 from Colorado. 



