56 
A Monograph of Culicidae. 
and cold accelerate and retard respectively the length of the 
various stages of Anopheles , just as in Culex, so that an approxi¬ 
mate time can only be given. 
During the past winter I found an abundance of Anopheles 
hifurcatus larvae of all sizes ; they appear to grow at this time very 
slowly. I first noticed them on November 3rd, when some were 
quite small, others about one-fourth of an inch long ; by December 
22nd only two out of a hundred had pupated. Those kept indoors 
developed a little faster, but no pupae appeared until December 
14th. This is the chief way that A. hifurcatus passes the winter. 
It does not seem to be usual for the larvae of A. maculipennis 
to occur during the winter in England; probably in mild 
weather the females, instead of hibernating, may deposit their 
eggs at once, thus producing a second brood, which would live 
through the winter and mature more rapidly in the spring. I 
noticed female A. maculipennis about as late as December 10th, 
and found a few larvae during the past winter. 
In Corethra the larvae live through the winter, the larval 
stage extending from October or November until March or April 
of the following year. The pupal stage lasts only a few days; in 
spring Meinert found it to be from four to five days, but later in 
the summer scarcely four. 
There is a second brood of larvae in the summer which 
develop more rapidly than the winter larvae, the period seldom 
exceeding six wrneks. The first brood of flies commence in 
March and April, the second in August, September, and 
November, but occasional specimens are known to emerge in the 
intervening period. 
HABITS OF ADULT MOSQUITOES. 
JS 
Mosquitoes present a great variety of habits, and certain 
species show great partiality for certain localities. 
The genus Megarhinus almost exclusively inhabit deep tropical 
forests, and therefore do not often come under the term mosquito. 
They sometimes, however, leave their arboreal haunts and come 
into the haunts of man, for Dr. Lutz writes me from Sao Paulo 
that he had seen a Megarhinus, probably M. haemorrhoidalis, in 
the town of Rio. 
That they sometimes attack man we gather from the fact 
that they have been sent in the collections to the Museum from 
