PSVCHK. 



A CONTRIBUTION TOWx\RD A KNOWLEDGE OF THE LIFE 

 HISTORY OF CULEX SOLLICITANS. PLATE i. 



BY JOHN B. SMITH, NEW BRUNSWICK, N. J. 



The life history of a mosquito is ordinarily supposed to be rather a simple 

 affair, and when egg, larva, pupa, and adult are known and the stage in which the 

 winter is passed, it is assumed that little more remains to be learned. Yet of at 

 least one species this is so little true, that our knowledge of the ordinary life cycle 

 is a mere introduction to a real history of the species. 



The species referred to is Culex solUcitans Wlk., which breeds abundantly 

 along the shore districts in New Jersey, and which I have had under close obser- 

 vation during a portion of the season of 1901, and almost the entire season of 1902. 

 Yet after carefully reviewing the results of the work done and the observations made, 

 it appears that there is at least one full season's work yet required to clear up the 

 questions left unsolved or raised by what has been already learned. 



The salt-marsh mosquito is, from the economic standpoint, the most important 

 species that occurs in New Jersey, and it is of New Jersey conditions that I intend 

 to speak here. It dominates the entire southern half of the State and occurs in 

 swarms where there is no chance of mosquito breeding for miles about, except in 

 casual rain pools — and there the larva is never found. I do not mean to contra- 

 dict observations made elsewhere, or to question conclusions drawn from such 

 observations : I mean only to state actual facts and the deductions I make from 

 them ! It is quite possible that elsewhere, under other climatic conditions, these 

 deductions may prove incorrect ; but it will need equally extensive observations to 

 demonstrate this. 



The species passes the winter in the ^gg stage. This is demonstrated nega- 

 tively by a failure to find adults at any time during the winter in quarters where 

 the species is dominant, and where other species of Culex and Anopheles may 

 be found. Positively it is proved by the fact that very early in spring, swarms of 

 minute larvae appear in winter-filled pools, as soon as the temperature reaches 50° 

 Fahrenheit or over, and when not an adult can be found on the closest search. 



Early in April (4) larvae pretty well grown were found in Cape May County 

 in pools, high above ordinary or even summer storm tides, formed by the heaviest 



