MOSQUITO BIOLOGY 225 



Mr. Brakeley kept a duplicate series of specimens under observation 

 at Lahaway, and his first pupa, from larvae thawed out of ice February 

 17, was obtained April 16, and became adult on the twenty-sixth. This 

 gives a period of fifty-eight days in active larval life, at an ordinary 

 indoor temperature, or sixty-eight days if the pupal period is counted. 

 Other pupae and adults developed and the pupal period ranged between 

 ten and twelve days. A small lot of specimens gathered April 7, began 

 pupating May 1, and these had an average pupal period of eight days. 



Altogether Mr. Brakeley sent me, prior to May 1, some fifteen to 

 twenty lots of larvae, numbering many hundreds of specimens. All these 

 were kept in the original pitcher leaf water and this never became foul. 

 It required the contents of from forty to seventy-five pitchers to make 

 a full pint of liquid, and the larvae numbered from one to twenty or 

 more in each leaf. Culture after culture was closed out during the sum- 

 mer; but though the conditions for all the larvae in a single jar were 

 absolutely the same, the rate of development varied in each individual. 

 One quart jar, containing nearly 200 larvae, received in early March, 

 developed adults throughout the summer, and this was not closed out 

 until September 13, 1901, six months after its receipt, when there were 

 yet a few larvae, two or three pupae, and one or two adults ! These lar- 

 vae had been surely hatched in November, 1900, and had remained in 

 that condition for certainly ten months, including the entire summer. 



May 31, June 1, and 2, were spent at Lahaway with Mr. Brakeley, 

 and during those days the swamps for some distance around were vis- 

 ited and dozens of pitcher plants closely examined. 



In the areas flooded during the winter by cranberry bog operations, 

 no larvae were found ; but as soon as the flood line was passed, larvae 

 were taken ; generally half a dozen or more to a leaf. But none occurred 

 except in the leaves. This point was tested very thoroughly throughout 

 the season and it is absolutely certain that this little species does not 

 occur anywhere outside of the receptacles formed by Sarracenia, except 

 by accident. In the colder, shaded parts of the swamp, where springs 

 occurred, larvae only were found. In the warmer areas pupae were com- 

 mon and, in some places, where water and moss surrounding the plant 

 were actually tepid, the insects had already emerged and nothing but 

 empty pupa shells could be found. It seems to be entirely a matter of 

 temperature, and in some of the coldest places, no transformations 

 would be likely to occur much before late June. It is certain that most 

 hibernating larvae live from early November to late May or early June, 

 a period of fully six months. No adults could be found and certainly 

 none made any attempt to bite. Nor could egg masses or young larvae 



