1915] Wheeler — ^1 New Boy-Inhabiling Varietii of Formica Fusca L. 205 



Formica fusca L. var. algida var. nov. 



Worker. Length 3.5-5.5 mm. 



Head not longer than broad, except in the smallest individuals, slightly narrowed 

 in front, with rather convex sides. Epinotum distinctly and often sharply angu- 

 late in profile. Petiole convex in front, flattened behind, with transverse, feebly 

 rounded, entire border, precisely as in the vars. neorufibarbis and gelida. Upper 

 surface of head and thorax much more opaque and more coarsely shagreened than in 

 these varieties. Frontal area shining. Gaster much more shining than in the 

 varieties mentioned, though sharply shagreened, its hairs short, blunt and sparse, 

 its pubescence much sparser and distinctly longer and coarser, except on the anter- 

 ior portion of the first gastric segment, where it is very fine and dense as in gelida 

 and neorufibarbis. Pubescence on head, especially on its sides, long and dilute. 

 Color variable; dark reddish brown; cheeks, mandibles and clypeus paler; gaster 

 and posterodorsal portions of head and in many specimens also the thorax 

 and petiole, black. Thorax, however, usually paler than the head and in many 

 Newfoundland specimens pale brownish red, as in neorufibarbis, but with a dark 

 cloud on the pro- and mesonotum as in gelida. In these specimens the pale color 

 extends also to the petiole and base of the first gastric segment. Other specimens 

 have the thorax dark brown, with paler and more reddish sutures. Legs reddish 

 brown, usually with the coxse, femora and tibi* dark brown or blackish, except at 

 the articulations. Antennae reddish brown, funiculi infuscated, except at the base. 



Female. Length 6..5-G.8 mm. 



Resembling the worker in pilosity and pubescence, except that the latter on the 

 gaster is even more dilute and longer and the surface of this region is more delicately 

 shagreened and more shining. The petiole is broader and more compressed antero- 

 posteriorly, with more acute border, which is entire and often slightly produced 

 upward in the middle. The color is similar to that of the lightest workers, the 

 thorax, petiole, legs and anterior and ventral portions of the first gastric segment 

 being clear brownish red. Pronotum with brownish anterior and posterior borders, 

 pleurae more or less clouded with brown; mesonotum with three more or less sharply 

 defined, longitudinal dark brown or blackish Ijlotches; metanotum and posterior 

 border of scutellum more or less infuscated. Wings colorless, with brown veins and 

 apterostigma. 



Maine: Kittery Point, in Sphagnum bog (R. Thaxter), type 

 locality. 



New Hampshire: Lafayette, 4,000 feet in Sphagnum bog (J. H. 

 Emerton); Mt. Washington, 3,840 feet (W. Reiff). 



Massachusetts: Petersham, in Sphagnum bog (Wheeler). 



New York: Bedford, nesting in dead leaf of Sarracenia, in 

 Sphagnum bog (Wheeler). 



Michigan: Porcupine Mountains and Isle Royale (O. McCreary). 



Ontario: Kenora (J. C. Bradley). 



Quebec: Saguenay R. (Geo. Engelhardt); Anticosti I., Mingan 



