Is a .Natural Migrant 



The mosquitoes are of economic importance because they breed 

 m such enormous numbers and because they are naturally migrants 

 and will fly in large broods for ten, twenty, or perhaps thirty mile9 

 from the marsh in which they breed. Sometimes they sweep un- 

 announced into an inland community like a huge conquering army 



Does Not Breed in Fresh Water 



In spite of the fact that these mosquitoes are so often found in 

 inland towns and cities, they always breed in salt or brackish water 

 The egg is deposited in the soft salt-marsh where it is floated out by 

 the high tides or rain. In a few hours the larva issues from the egg 

 and wiggles 

 around in the 

 water of the 

 pool. After 6 

 days to 3 weeks, 

 depending on the 

 rainfall and 

 temperature, the 

 larva becomes a 

 pupa just as ex- 

 plained in the 

 case of the house 

 mosquito, and in 

 a few hours the 

 full fledged adult 



appears. It is strong of wing and after a day or two starts its migra 

 don in search of food and shelter. This mosquito does not ordinarily 

 enter the house, but confines its visits to the garden and porch, where 

 it is especially active about dusk. 



Inland Swamp Mosquito 



In the inland swamp group we find the fresh-water swamp mo!> 

 quito, Aedes sylvestris, and also that bred in the woodland pool, 



Aedes stimulans. There are others, of 

 course, but these will serve as types. The 

 swamp mosquito winters in the egg at the 

 bottom of the pool in which it breeds. 

 Early in the spring the eggs hatch and the 

 larvae appear. 



The sylvestris is a small mosquito with 

 a narrow white band at the joints of the 

 legs and a noticeable indentation in the 

 white markings on the abdomen. This con 

 striction on the abdomen gives the ap- 

 pearance of a series of little "letter B's" on 

 the back of the mosquito and is the dis- 

 Dlunctiv/Ma^ Sm&n7*ith tiriguishing feature of this species. This 

 oarrow white band at joints of mosquito is especially prevalent during wet 



legs; indentation in white mark- ^ . . y • i i i . * 



ngs on abdomen, resembling series Seasons f Or it IS quick tO take advantage 01 



temporary rain-pools as well as the larger 



Fig. 6 — Life History of the Salt-Marsh Mosquito 

 Compare with Figure 1 and note difference in egg stage 



Fig. 7 — The Fresh-Water 



Swamp Mosquito 

 {Aedes Sylvestris Theob) 



of little 'letter B's. 1 



