526 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 
flat posterior surface, cordate when seen from behind, broad above, 
narrow below, its edge thin and sharp and narrowly excised in the 
middle. 
.Head and thorax opaque; gaster very feebly shining. 
Hairs yellow, somewhat less abundant than in the typical cinerea, 
absent on the sides of the head and mesopleurae. Pubescence gray- 
ish, dense, but more delicate than is the tyical form, especially on 
the head and thorax, so that the surface is much more exposed. 
Light yellowish red; top of head or at least the ocellar triangle, 
a large spot on the pronotum, the upper surface of the gaster and the 
tips of the funiculi brown. 
Described from a dozen workers taken at Rockford, Illinois from a 
single colony occupying a very low mound-nest not unlike those con- 
structed by the var. neocinerea. ‘This variety is extremely close to 
the var. zmitans, but differs from it in lacking the prominent erect 
hairs on the sides of the head and thorax and in the slightly less abun- 
dant hairs on other parts of the body. 
110. F. CINEREA CINEREA var. LEPIDA, var. nov. 
WorkeER. Length 3.5-6.5 mm. 
Very similar in the structure of the thorax and petiole to the typical 
European cinerea, the epinotum being rather low and rounded, espe- 
cially in smaller workers, and the petiole narrow and blunt. 
The sculpture and pilosity are also very similar to the European 
type, the erect hairs being present on the sides of the head although 
absent on the pleurae. Legs with small, erect, scattered hairs on their 
extensor surfaces. The pubescence is dense and glistening white, 
even more silvery than in the European form, most conspicuous on 
the gaster though equally dense on the head and thorax. 
Color reddish yellow; antennae darker, posterodorsal surface of head 
blackish brown; gaster brown above, paler than the top of the head 
and sometimes scarcely darker than the thorax, which may be very 
feebly infuscated. 
Described from numerous specimens taken by Mr. J. C. Bradley 
at Blue Lake, Humboldt County, California. Except in color, this 
is the most closely related of all our North American varieties of 
cinerea to the typical form. It also closely resembles the subspecies 
pilicornis in general appearance and color, but may be readily distin- ~ 
guished by the absence of erect hairs on the antennal scapes and eyes 
and the less abundant pilosity of other parts of the body. 
