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 tinger the pupa at once wriggles violently away, returning 

 shortl}' to the surface for aii'. 



The duration of the pupal stage in Anopheles varies according to the 

 weather. Five days was the mininiuni 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 AnophAe>^ qwHlrhaaculatus in 

 the generation studied b}^ 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 

 Oulex pungens through an entire generation in the latter part of June, 

 1895, in ten daj^s. 



NATURAL BREEDING PLACES OF ANOPHELES. 



Having accomplished the preliminary work of studying different 

 stages of growth of Anopheles by breeding from captured females, w^e 

 were enabled to become familiar with the larvae and pupas so as to 

 recognize them readily and it was then not difficult to find the natural 

 breeding places. The first l)reeding place discovered was in Maryland, 

 and the larvae found there were those of what is probably A. puncti- 

 pennis. They closely resemble the corresponding stage of A. qnad- 

 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. 

 (jnadrimacidatus 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 larvoe were found resting at the surface of fig. ii .—Annpheies 

 the water, and occasionallv darting from one spot to punctipcnnis: 



11 . 1 1-1 1 1 Head of full- 



another. All ot those little pools were abundantly sup- grown larva from 

 Dlied with algae, and from specimens brought in Mr. above— enlarged 



^ ' *^ * (original). 



A. F. Woods has found that they ])elong to the genus 

 Mougeotia. There were also 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 larvre of ^1. (piad- 

 rlTnaculatus yifQVQ found. Algte also occurred here and Mr. Woods has 

 determined them as beloniiinu' to the same genus Mougeotia. 11' 



