THE MOSQUITOES OF THE SOUTHEASTERN STATES 43 



classification is similar except that the subgenus Taeniorhynchus 

 ( = Culicelsa) is also recognized by him to include the species 

 taeniorhynchus, sollicitans, mitchellae, and atropalpus. 



AEDES AEGYPTI (L.) 



(Syn., Stegomyia fasciatus F., Culex calopus Meig., C. argenteus Poir., etc. ; the yellow- 

 fever or dengue-fever mosquito) 



The adults are rather small and dark, with conspicuous rings of 

 white scales on the tarsi, and patches of white on the sides of the 

 thorax and abdomen. The lyre-shaped pattern on the mesonotum 

 (fig. 12, A), formed of lines of white scales, is characteristic of the 

 species. 



This species is the most thoroughly domesticated of any of the 

 mosquitoes and apparently greatly prefers the blood of man to that 

 of other animals. It breeds almost exclusively in artificial water 

 containers in the vicinity of dwellings or in the dwellings them- 

 selves. The larvae are found occasionally in tree holes and similar 

 natural collections of water, but so far as known the eggs are never 

 deposited in ground pools. The eggs are usually laid on the sides of 

 the receptacle just above the water line, or on the surface of the 

 water. It appears that places which are of solid material at the 

 water line are selected for oviposition. In Orlando, Fla., the writers 

 have found the larvae abundant at times in the underground street 

 catch basins, which, although partly filled with sand and dirt, were 

 lined with brick or concrete. Fairly clean water is preferred, and 

 sewage-polluted water in wooden or concrete cesspools is not a favor- 

 able breeding medium. The eggs are able to withstand drying for 

 long periods, and hatch very quickly when the receptacle is filled 

 with water. 



The adults are abundant during the summer in cities and towns 

 throughout the South and are troublesome house pests. Biting is 

 confined largely to the daylight hours, especially early in the morning 

 and late in the afternoon, and the females seem able to gain entrance 

 even into well-screened houses. They are wary biters and are espe- 

 cially annoying about the ankles. Aedes aegypti is thought to have 

 been the only species involved in the epidemics of yellow and dengue 

 fevers in the United States, although other species in other countries 

 have been proved capable of transmitting both these diseases. 



The adults have been kept alive in the laboratory for several 

 months, and in the summer they probably live longer than any other 

 of the southern species. They are very susceptible to cold, however, 

 and are said to die out at temperatures below about 40° F. The eggs 

 are more resistant, but the species probably does not overwinter in 

 the United States except in the extreme southern part. Each sum- 

 mer it becomes widely dispersed into territory farther north, prob- 

 ably by carriage in trains, boats, etc. Although the adults are strong 

 fliers, the usual flight range is considered to be not more than a few 

 hundred feet. 



The control of this species is discussed in the section on Mosquito 

 Control (p. 24) . A more extended account of its life history may be 

 found in a bulletin by Howard (66). 



