The Mosquitoes of New Jersey 41 



year (1904) ; but that is probably the southern Hmit of their dom- 

 inance, and in ordinary seasons it does not extend so far. Just 

 why they should be more plentiful on the northern marshes I do not 

 know, nor what prevents their development along the southern 

 shore." 



Since these words were written investigations that throw light on 

 this matter have been completed. It has been shown by Chidester- 

 that A. cantator thrives in waters of comparatively low salinity (6 

 to 8 per cent) which prevails throughout the New Jersey coast in 

 the spring and that A. sollicitans thrives in water of high salinity ( 10 

 to 15 per cent) which prevails during the latter part of summer. A 

 further proof of this factor is found in the fact that the brackish 

 marshes along the upper courses of our rivers breed A. cantator 

 throughout the entire season. 



It seems, therefore, reasonable to believe that the distribution of 

 these two species in point of time is mainly dependent upon the 

 salinity of the marsh waters in which they normally breed. High 

 salinity appears to inhibit the hatching of the eggs and the develop- 

 ment of A. cantator while it favors the development of A. sollicitans. 

 Low saUnity appears to inhibit the hatching of the eggs and the de- 

 velopment of A. sollicitans while it favors the development of A. 

 cantator. 



It seems likely to the writer that the inhibition of egg hatching is 

 probably the more important because an area which in spring gives 

 off broods of A^. cantator. as the salinity rises may give off a brood 

 oi A. sollicitans. 



The Unbanded Salt-Marsh Mosquito 



(Culcx salinarius Coq.j 



Recognition Marks 



This species may be distinguished from Culcx pipicns by its 

 darker and more lanky appearance, but this difference becomes 

 clearly distinguishable only when a long series of fresh specimens 

 of each species is at hand. When the mosquito becomes worn, or is 

 present in small numbers, it can be separated from C. pipicns only by 

 a careful comparison such as outlined on page 24. 



The larva is found in pools on the salt marsh or on adjacent up- 

 land. The wriggler is much like that of the house mosquito, differ- 



^Chidester, F. E., 1916. The influence of salinity on the development of 

 certain species of mosquito larvae and its bearing on the problem of the 

 distribution of species. N. J. Agr. Exp. Sta. Bui. 299. 



