DOMESTIC MOSQUITOES 



moistened, however, they may remain dormant for weeks or even 

 months. When immersed in water they promptly hatch. Under most 

 favorable conditions the wigglers (fig. 4) develop in 6 to 8 days and 

 change into the less active tumbler 

 or pupa stage (fig. 5), from which 

 the adult insect (title page illustra- 

 tion and fig. 2) emerges about 2 

 days later. The complete develop- 

 ment from egg to adult mosquito is, 

 therefore, 9% to 12 days, or longer 

 in cooler weather or under less 

 favorable conditions. 



The house mosquitoes have a similar developmental period, but 

 they differ markedly from the yellow-fever mosquito in the egg stage. 

 The eggs are laid in boat-shaped masses or rafts (fig. 6) directly on the 

 surface of the water and, if dried, soon lose their ability to hatch. 



Biting Habits 



Figure 3.- 

 mosquito. 



Egg of the yellow-fever 

 About 100 times natural 



Figure 4. — Larva, or wiggler, 



of the yellow-fever mosquito. ^y^ n . 

 About 10 times natural size. 



Only the female mosquitoes bite. 

 The males, which have poorly developed 

 mouth parts, drink water and feed on 

 the nectar from flowers. 



The yellow-fever mosquito bites 

 mainly during the daytime, especially 

 late in the afternoon or early in the 

 morning. In cloudy weather or in the 

 darker portions of rooms it may bite 

 throughout the day. The house mos- 

 quitoes are night biters and hide away 

 in closets and other dark places during 

 the day. 



Flight Habits 



The domestic mosquitoes are not long- 

 distance fliers. When abundant about a 

 house, they are usually to be found 

 breeding in the vicinity. This is parti- 

 cularly true of the yellow-fever mosquito. 

 The northern and southern house mos- 

 quitoes may travel a mile or so from the 

 place where they breed. The yellow- 

 fever mosquito seldom travels more than 

 a few hundred yards. It is freely carried 

 about, however, in trains and boats, and 

 in automobiles, airplanes, and 

 dirigibles. 



Overwintering 



The northern and southern house, or rain-barrel, mosquitoes over- 

 winter in the adult stage. Only the fertilized females survive. They 

 hide away in protected places in out buildings, basements, unused rooms 

 in houses, street drain traps, and storm sewers. They remain rela- 

 tively inactive in cool places, but in warmer places breeding may con- 



