WHEELER: ANTS OF THE GENUS FORMICA. 497 
ences between the form which I described as the var. glacialis from 
Maine and the true European fusca. The wings of the males and 
females in the American form are perhaps slightly darker, but the tint 
is variable in European specimens. ‘The sculpture, color, and pubes- 
cence are identical in the two forms. The specimens from Newfound- 
land, including in all probability those from St. Pierre and Miquelon, 
Newfoundland, mentioned by Emery (Zool. jahrb. Syst., 1893, 7, p. 
660), and the specimens from Nova Scotia and New Brunswick agree 
very closely with the cotypes from Maine. ‘The western forms are 
often a little more like subsericea in pubescence and may be regarded 
as transitional to that variety. Should it be possible on further study 
to detect any satisfactory differences between American and Eurasian 
specimens, the term glaczalzs would, of course, have to be reinstated. 
The colonies of the American fusca are often much larger than those 
which I have seen in Europe. In both continents it nests under stones 
or logs or in rude craters or small earthen mounds. The workers are 
extremely timid. This timidity, which characterizes all the varieties 
and subspecies of F. fusca, together with its extreme fecundity, has 
made it an ideal host for a large number of the parasitic species of 
Formica of the sanguinea, rufa, microgyna, and exsecta groups. 
81. F. FUSCA FUSCA var. GLEBARIA Nylander. 
F. glebaria Nylander, Acta. Soc. Fennica, 1846, 2, p. 917, 8 9, taf. 18, 
fig. 23; Forster, Hymen. stud., 1850,1, p. 31, 8 9 o&. 
F. fusca var. glebaria Emery, Deutsch. ent. zeitschr., 1909, p. 196, 8 9; 
Karawajew, Rev. Russe ent., 1909, p. 268. 
F. fusca subsp. glebaria Emery, Deutsch. ent. zeitschr., 1912, p. 672. 
Worker. Length 4-6.5 mm. 
Differing from the typical fusca in color and pilosity. The body is 
deep brown or at any rate not deep black, and the pubescence is longer 
and more abundant, especially on the gaster, so that the body is dis- 
tinctly silky. The front of the head, the sutures of the thorax, the 
scapes, and articulations of the legs are pale and more yellowish or 
reddish. 
FeMaLeE. Length: 7-9 mm. 
Resembling the worker in color and pilosity. The gaster is not 
smooth and shining as in the typical fusca but subopaque and covered 
with much denser pubescence and appearing glossy or silky. Wings 
distinctly infuscated at their bases. 
Mae. Length 8-9 mm. 
