WHEELER: ANTS OF THE GENUS FORMICA. 505 
Massachusetts: Wellesley (A. P. Morse); Blue Hills (Wheeler). 
Connecticut: Colebrook (Wheeler). 
New York: Ithaca (J. C. Bradley); Bedford (Wheeler). 
Ontario: Guelph, Port Stanley (W. H. Wright). 
Quebec: Kingsmere (Wheeler). 
British Columbia: Howser, Carbonate, Selkirk Mts. (J.C. Bradley) ; 
Mt. Goodsir, 7,000 ft. (E. Whymper). 
Alberta: Vermillion Pass, 5,000-6,500 ft. (E. Whymper). 
This form differs considerably in the amount of pubescence on the 
gaster. The specimens from New Mexico, especially, have the pubes- 
cence nearly as dense and abundant as in subsericea, but as the ground 
surface is coppery and partially visible I have included them in this 
variety. They are, perhaps, the form described by Viereck as var. 
densiventris, but his original description based on two workers from 
Beulah, New Mexico (8,000 feet), is far from clear, and I have not 
been able to examine the types. Specimens from Rockford, IIl., agree 
very closely with Emery’s description based on material from South 
Dakota and Connecticut. The worker specimens from Alta Peak, 
Calif., are very small and the pubescence is very delicate. They are 
decidedly bronzy, but in other respects might be referred to the 
typical fusca. 
F. subaenescens nests under stones in cold, shady woods. Like the 
var. argentea it is rare and sporadic at lower altitudes and latitudes 
in the transitional zone and is evidently a boreal form, slightly more 
eurythermal than the true fusca. 
88. F. FUSCA FUSCA var. GELIDA, var. nov. 
F. fusca var. neorufibarbis Forel, Ann. Soc. ent. Belg., 1904, 48, p. 1538, 8 9; 
Pergande, Proc. Wash. aead. sci., 1900, 2, p. 519; Wheeler, Bull. Amer. 
mus. nat. hist., 1906, 22, p. 344; Ants, 1910, p. 570. 
WorkKeER. Length 2.5-5 mm. 
Head and thorax subopaque, frontal area and gaster shining and 
rather smooth. Hairs as in the typical fusca, pale yellow; pubescence 
much sparser, not only on the gaster but also on the head and thorax, 
so that the ground surface of the body is fully revealed. This is rather 
densely and sharply shagreened on the head and thorax, but very finely 
shagreened and sparsely punctate on the gaster. 
Reddish brown, posterior half of head above black, sometimes with 
a bronzy reflection. Gaster often as dark as the top of the head. 
Thorax more or less infuscated. In large workers the infuscation is 
