82 
MAT.ARTA 
for A. quadrimaculatus and found marked 
daily migration among shelters. A. cru¬ 
cians (possibly bradleyi) was reported by 
King, Bradley and MacNeel (1939) as mi¬ 
grating several miles when intense breeding 
occurred. On the Mississippi coast, flights 
of A. crucians from islands situated from 3 
to 12 miles off shore were reported by 
Barber, Komp, and Hayne (1924), and 
MacCreary and Stearns (1937) have re¬ 
corded flights of this species to two light¬ 
houses situated 3.2 and 5.5 miles, respec¬ 
tively, from shore. Freeborn (1932) states 
that in California “prehibernation” forms 
of A. maculipennis appear during October 
and early in November, which are darker 
and more robust than the summer forms 
and migrate long distances from their 
breeding grounds before entering shelters. 
Although they become active on warm days 
in the winter, they do not develop eggs un¬ 
til after an “emergence” flight during the 
middle of February. At this time they in¬ 
fest areas both suitable and unsuitable for 
breeding. From studies on overwintering 
individuals of A. quadrimaculatus made at 
Fort Jackson, La., Hinman (1934c) con¬ 
cluded that the enormous number of fe¬ 
males which congregate in the old fort in 
November probably migrated there from 
considerable distances, since there was a 
scarcity of breeding places nearby, and that 
they undergo a sort of pseudohibernating 
period of 2 to 3 months. It may be signifi¬ 
cant that very few of A. crucians and none 
of A. atropos were noted in this winter re¬ 
treat even though these species breed 
abundantly in the vicinity. 
Hibernation. There is probably no true 
hibernation of Anopheles quadrimaculatus, 
A. punctipennis, or A. crucians in the more 
southern part of their range, as numerous 
authors have reported that these species 
become active during warm periods in the 
winter. In cold weather adults seek shel¬ 
ter in unoccupied houses, caves, hollow 
trees, and other such places, where they 
become inactive. Larvae and pupae are 
also to be found throughout the winter, and 
it is probable that these species pass the 
winter to some, extent in the aquatic stages, 
as well as by overwintering females. Bal¬ 
four (1928) found that some larvae of A. 
crucians passed the winter in North Caro¬ 
lina during the winter of 1926-27 when the 
temperature over a 10-day period had a 
mean minimum of 24° F and an absolute 
minimum of 12.5° F. Larvae of A. quadri¬ 
maculatus and A. crucians were collected 
in every month except January, but no A. 
punctipennis were found in January or 
February. Hinman and Hurlbut (1940) 
stated that in the Tennessee valley A. 
quadrimaculatus passed the winter chiefly 
as inseminated females. Hibernating fe¬ 
males in caves survived periods up to 69 
days without food. 
Matheson and Hurlbut (1937) discovered 
that two forms of eggs are laid by A. 
walkeri, which they called summer eggs and 
winter eggs. In New York State the former 
hatched normally soon after oviposition and 
could not withstand freezing temperatures, 
but the latter did not hatch unless sub¬ 
jected to freezing temperatures. It is be¬ 
lieved that the winter eggs are the only 
means by which this species survives the 
winter in New York. Winter eggs of A. 
walkeri from Tennessee showed a marked 
instability and the greater part of those 
obtained hatched soon after oviposition 
(Hurlbut 1938b). 
Owen (1937) states that in Minnesota 
the females of A. maculipennis ( occiden¬ 
tals s) hibernate. He found that in two out 
of four caves under observation the places 
selected for hibernation did not afford ade¬ 
quate protection, as the adults were killed 
by becoming frozen in ice on the walls. In 
the anteroom of a larger cave all died. 
Apparently he assumes that those in the 
deeper recesses of the large caves success¬ 
fully passed the winter, although they were 
not located. 
Enemies of adults. Birds, bats, toads, 
frogs, and lizards, as well as insects and 
spiders, are included among adult preda¬ 
tors of anophelines, and protozoans, filaria 
embryos, other nematodes, and trematodes 
among the parasites. Hinman (1934b) has 
prepared a summary of the available litera¬ 
ture on the predators and Boyd (1930a) 
