138 3I0SQUIT0ES 



bite of tliis species is worse in the autumn than in the 

 summer, and that it breeds in cisterns, which, in that sec- 

 tion, are in universal use for obtaining- drinking-water. 

 Mr. Pratt made some interesting observations on the 

 species at an Atlantic Coast summer resort, in a latitude 

 of about 36° 50' N., and succeeded in obtaining the larvae 

 and pupae, from which the accompanying drawings were 

 made. At that point he also found it breeding in the 

 rain-water tanks. Neither larva nor pupa differs greatly 

 from that of the species of the genus Culex, the charac- 

 teristics of which have been described in an earlier 

 chapter. It maj^ be of interest to note that before this in- 

 sect was connected with yellow fever, I learned that in 

 certain of the AVest Indies and in Louisiana it is known 

 as the " day mosquito." Dr. Yeazie, of New Orleans, and 

 Dr. St. George Gray, of St. Lucia, communicated this fact. 

 The latter writes that it is very vigorous and troublesome 

 in the early afternoon, from 12 M. to 3 P.M., after which it 

 takes a rest until 9 or 10 p.m. 



It should be stated emphatically that it is probable that 

 this species has a wide range south of Mason and Dixon's 

 line, and that it probably occurs everywhere in what is 

 termed the lower austral life zone, extending to some ex- 

 tent into the upper austral zone. This fact, however, and 

 the existence of this mosquito in a given locality, does 

 not mean that there is any danger in such localities of 

 yellow fever, unless one or more cases of the disease are 

 brought into the locality and exposed in such a way that 

 mosquitoes have the opportunity to suck their blood and 

 fly away untrammelled to some healthy individual. 



