a handbook of the mosquitoes of north america - Systematic Catalog ...

44 MOSQUITOES OF NORTH AMERICA
caves, tree-holes, etc., where a certain degree of moisture and
semi-darkness obtains. During the hibernation period, the
females are normally inactive, resting quietly, closely hugging
the surface on which they rest. In houses, Alzoplaeles @tic-
tipenrzis and Culcx ~~/&Rs may frequently invade the warmer
rooms and I have taken both species in the act of sucking
blood.
The great majority of our species hibernate in the egg stage.
This is true of practically all the species of Aedes and Psoro-
plzora. The yellow fever mosquito cannot withstand cold
weather so that it breeds only in the warmer portions of the
south. Its occurrence in more northern locations is due to its
transportation during the summer season. Though it has been
repeatedly introduced into California, it never breeds there on
account of the cool nights. Its general distribution is to about
38” N. latitude and its breeding in this area is limited by local
climatic conditions. As far as known, all our Tlzeobaldia spe-
cies, except T. melanwa, hibernate as adults. T. melanwra
passes the winter as larvae in the bottom of the pools in which
they breed. Wyeowzyia smithii, the pitcher plant mosquito,
hibernates as larvae frozen in the water contained by the
leaves.