FORMICA. 321 



and mesonotum ; and in the small workers the brown colour is sometimes 

 spread over the whole body as in glebaria. 



Structure and form much as in fusca, more hairy, and with longer and 

 closer pubescence. Head opaque, not quite so dull as thorax ; clypeus dis- 

 tinctly carinate ; frontal area punctured. Thorax opaque ; pronotum fur- 

 nished with very distinct scattered outstanding yellow hairs, in both large 

 and small specimens. Scale large, broad, rounded, sometimes with a few 



Fig. 91. Side view of thorax of Formica rufibarbis ^. 



outstanding hairs ; gaster with scattered outstanding yellow hairs. Long. 

 4-6-7-5 mm. (4-7-5 mm. teste Wheeler.) 



$ Cheeks, clypeus, frontal area, mandibles, scapes and base of funiculi, 

 pronotum, mesonotum and scutellum in part, scale, apex of gaster and legs lighter 

 or darker yellowish red ; rest of head, mesonotum with three longitudinal patches, 

 scutellum, post scutellum and gaster blackish brown. 



Structure and form of fusca. Thorax with outstanding hairs, longer and 

 more abundant than in the fusca vars. Wings greyish, veins brown yellow, 

 pterostigma darker. Long. 9-10 mm. (9-11 mm. teste Wheeler.) 



$ Black ; legs yellow with nearly the whole of the tarsi, and base of femora 

 blackish (sometimes only the extreme base of the femora, and the apex of the 

 tibiae are dark, or the whole of the legs may be mostly blackish) ; genitalia reddish 

 yellow. Shape and structure as in fusca ; duller in appearance. Head with 

 more distinct decumbent yellow hairs on cheeks and clypeus than in fusca or 

 its vars. Thorax with distinct outstanding yellow hairs. Scale only slightly, 

 or widely but not deeply emarginate, furnished with outstanding hairs ; 

 gaster more closely punctured than in fusca, with shorter closer pubescence, 

 and some outstanding yellow hairs. Wings a little darker than in the $. 

 Long. 8-5-11-8 mm. (9-10 mm. teste Wheeler.) 



Original description of Formica rufibarbis Fabricius [Ent. Syst. 

 2 355 (1793)] : 



" F. oblonga nigra ore thoraceque runs. 



Habitat in Gallia. 



Media. Antennae nigrae. Caput nigrum ore late rufo, qui color ad latera 

 extenditur. 



Mandibulae tamen nigrae. Thorax rufus, immaculatus. 



Squama petiolaris ovata, obtusa. Abdomen ovatum, atrum, immaculatum. 

 Pedes nigri." 



Habitat. 



Widely distributed through Europe and Northern Asia, and 

 occurring in Sardinia, though absent from the smaller Mediter- 

 ranean islands. It is a distinctly xerothermal form and in the 

 Alps does not reach such an elevation as the typical fusca. Accord- 

 ing to Ruzsky, however, it occurs at an altitude of 3000 m. in the 

 Caucasus, and according to Forel even higher in the Himalayas 41 . 



