26 
in view of the care with which the figures accompanying this article 
have been drawn. The air tubes no longer open at the anal end of the 
body, but through two trumpet-shaped sclerites on the thorax, from 
which it results that the pupa remains upright at the surface, instead 
of with the head downward. ‘There is a very apparent object in this 
reversal of the position of the body, since the adult insect issues from 
the thorax and needs the floating skin to support itself while its wings 
are expanding. 
In general, the adult msects issue from the pupe that are two days 
Fie. 3.—Culex pungens: Full-grown larva at left, pupa at right—enlarged (original). 
old. This gives what is probably the minimum generation for this 
species as ten days, namely, sixteen to twenty-four hours for the egg, 
seven days for the larva, and two days for the pupa. The individuals 
emerging on the first day were invariably males.. On the second day 
the great majority were males, but there were also a few females. The 
preponderance of males continued to hold for three days; later the 
females were in the majority. In confinement the males died quickly; 
several lived for four days, but none for more than that period. The 
females, however, lived for a much longer time. Some were kept alive 
