41 
be noticed. The pupa of Anopheles is quite as active, when disturbed, 
as is that of Culex. If one touches the near-by surface of the water 
with the finger the pupa at once wriggles violently away, returning 
shortly to the surface for air. 
The duration of the pupal stage in Anopheles varies according to the 
weather. Five days was the minimum observed during June, although 
several specimens remained in this stage for ten days. The adults issue 
as do those of Culex. 
The entire life round, therefore, of Anopheles quadrimaculatus in 
the generation studied by the writer is as follows: Egg stage, three 
days; larval stage, sixteen days; pupal stage, five days; making a total 
period in the early stages of twenty-four days. It should be stated, 
however, that during the early larval existence toward the end of May 
there occurred nearly a week of cool weather, so that it is certain that 
in the hot season in July and August the growth and transformations 
will be more rapid. It will be remembered that the writer traced 
Culex pungens through an entire generation in the latter part of June, 
1895, in ten days. 
NATURAL BREEDING PLACES OF ANOPHELES. 
Having accomplished the preliminary work of studying different 
stages of growth of Anopheles by breeding from captured females, we 
were enabled to become familiar with the larve and pupe so as to 
recognize them readily and it was then not difficult to find the natural 
breeding places. The first breeding place discovered was in Maryland, 
and the larve found there were those of what is probably A. puncti- 
pennis. They closely resemble the corresponding stage of A. quad- 
rimaculatus except in the maculation of the head. A figure of the 
head of this form is shown here (fig. 17) in order that it 
may be compared with the corresponding figure of A. 
quadrimaculatus shown in fig. 15. This first breeding 
place of Anopheles was a small permanent stream run- 
ning through the woods which had here and there broad- 
ened out into little shallows, and in these shallows the 
Anopheles larve were found resting at the surface of re. 17—Anophetes 
the water, and occasionally darting from one spot to Be 
another. All of these little pools were abundantly sup- — grown 1arva from 
plied with alge, and from specimens brought in Mr. pee 
A. F. Woods has found that they belong to the genus 
Mougeotia. There werealso many Diatoms present. The next natural 
breeding place found was in pools about a disused spring in Virginia. 
At the sides of the spring were several more or less permanent pools 
of considerable depth (8 to 10 inches). Here the larve of A. guad- 
romaculatus were found. Algze also occurred here and Mr. Woods has 
determined them as belonging to the same genus Mougeotia. The 
74 
