REPORT ON MOSQUITOES. 269 



The young larva in captivity, when undisturbed, has the habit 

 of using- the anal siphon as a pivot around which it swings with 

 head bent upward so as to feed on material just below or at the 

 surface. In all stages the larva is more nearly parallel to the sur- 

 face than most other species. 



Habits of the Barly Stages. 



This is the earliest and latest of the species that winter in the 

 eg-g stage: earliest as to both adult and larva, and latest as to 

 larva only. The extreme records for either direction are from 

 Mr. J. Turner Brakeley, who found recently hatched larvcC in 

 November and again in the February following. That the 

 February larvae did not hibernate as such is abundantly proved 

 by the almost daily collections made during February, 1903. by 

 the fact tliat larvae developed in water with a portion of the mud 

 bottom from woodland pools and, finally, by the fact that I found 

 the eggs in some samples of mud from the bottom of breeding 

 pools sent in to me for examination at my request. 



The first find was made February 6th in a jar in which larvae 

 of C. nielanuriis Avere being bred. These larvae were collected 

 February 3d, and at that time no^ trace of small wrigglers was 

 noted. One example found on the 6th seemed as if it had just 

 hatched, and there is no reasonable doubt that the transfer from 

 the breeding pools to the house temperature induced develop- 

 ment. Collections were made in the field February 8th in a sleet 

 stomi, the pools ice covered and the water temperature 36 de- 

 grees. Twenty-five specimens, all of them' apparently just out 

 of the tg^, were collected, and these mostly out of the bottom mud 

 where they seemed to be in hiding. To test this yet further, a 

 supply of bottom material was secured February 9th, and in less 

 than twenty-four hours minute larv^ were found in each of the 

 breeding jars into which it was placed. It is positively proved, 

 therefore, that during the early days of February, in water just 

 above the freezing temperature, the lai-vae of canadensis may 

 and do hatch from the tgg under entirely natural conditions. 

 Hatching may be hastened by disturbing the material in which 

 the eggs are laid, and this probably accounts for the larvae first 

 found in the jars. 



February, 1903, was a cold month and the breeding pools in 

 which the larvae were found became iced over several times, so 

 as to bar absolutely all access to the surface ; nevertheless, there 

 was nO' apparent decrease in the number of specimens, but, on 

 the contrarv, a continuous increase. Artificial tests were made 



