1914] . Smith—The Development of Anopheles punctipennis Say 7 
of observation of Anopheles in Russia, mating occurs in the autumn 
except in a few isolated cases, where it occurs after hibernation. 
The hibernating females deposit the eggs during the whole of the 
next spring and summer, and the September and October larvee 
result from the isolated cases. Accordingly, he is of the opinion 
that there is but one generation in a season, the newly developed 
forms not depositing eggs until after hibernation. There has been 
insufficient study of this subject. 
The eggs are laid singly and a number of times by each indi- 
vidual during a single breeding season. Dr. Duprée found that 
specimens of A. punctipennis, which were kept in the laboratory 
and supplied with blood, would lay at six or seven different 
periods, with a total number of more than 2,000 eggs. As many 
as nine layings were noted in one case. The eggs, from 100 to 300 
at a time, are deposited separately, or sometimes in clusters of 
just a few. They are apt to float below the surface, although 
some of them are on the surface. Stirring the water will bring a 
good many eggs to the surface, from which they soon disappear 
again. They seem not to possess so perfect a means of keeping 
afloat as is recorded of the eggs of Anopheles maculipennis, which 
has the light clasping membrane about the whole rim of the egg. 
In A. punctipennis this clasping membrane is restricted to the 
sides. It is very delicate, apparently, for in several instances it 
was badly broken, or had perhaps been eaten away. A young 
crustacean was seen to devour the clasping membrane from one 
side of an egg. 
The egg (fig. 1) is .55 mm. in length, mottled in appearance, 
and dark brown in color with blotches of silvery white. At the 
end are scattered light and dark spots, the former of which have 
been called “knobs” and which are arranged in a more or less 
regular pattern. Sometimes the eggs lose nearly all their dark 
color, and float. They float with the concave surface underneath. 
The larva breaks through the convex surface at the larger end, 
leaving a little fragment of the shell cut out on three sides, and 
bending over like a little canopy at one end of a little boat. 
First Stage of the Larva (fig. 2). At first the young larva spends 
periods of time quietly. Suddenly it will start a strong current of 
water by means of the rotary brushes, which are large in propor- 
tion to the remainder of the body. These are fully developed 
