1892.] Entomology. 871 
ENTOMOLOGY, 
Habits of Prenolepis imparis Say.—The Winter Ant.— 
This ant rarely appears outside of its nest during the heat of the day, 
from 12 to 4 o'clock (although an occasional individual comes out in 
the middle of the day), while the little brown Lasius and black Formica 
are active at that time. It is one of the commonest ants in the North- 
ern States, and is among the earliest to appear in the spring, occasion- 
ally appearing during mild winters, but becomes less active in summer, 
avoiding the heat. 
The males and females take their marriage flight in April, as Say 
has recorded and as I have many times observed, the latest date at 
which I have found the winged female being May 9. It seems proba- 
ble, therefore, that the males and females must pass the winter as pups 
or very advanced larve, although in nearly all our other ants they 
hibernate in a much earlier stage and the mature forms do not appear 
until much later in the season. 
This ant bears much resemblance to some species of Lasius, but may 
at once be distinguished by the absence of a discoidal cell in the wings 
and the different form of the petiole of the abdomen. The genus 
Prenolepis resembles Tapinoma in having the scale of the petiole in 
the worker nearly concealed by the base of the abdomen, but the 
male and female may be distinguished by having no discoidal cell. 
The male and female of this species were described by Say under the 
old genus Formica and it has not since been identified. Roger in his 
“ Verzeichniss” has queried whether it might not be a Lasius ; it is, 
however, identical with the European type of Prenolepis, P. nitens 
Mayr, which its author has already recorded from North America. 
Roger, in 1859, described the female, and in 1862 the worker from 
European specimens under the name Formica crepusculascens, but at 
the latter date recognized the synonomy with P. nitens. : 
Tapinoma polita, described by Smith from a single worker found in 
Wales, has been placed by Roger as a synonym of P. nitens, but 
apparently in error, as Smith compared his species with nitens and 
pointed out differences in the antennæ, the scale, and the color of 
abdomen, which appear to be at least of specific value. T. polita was 
omitted in Mayr’s Index. Mayr, in “Europ. Form,” p. 52, note, con- 
siders polita a synonym of nitens. The synonymy is then : 
