THE MOSQUITOES OF THE SOUTHEASTERN STATES 49 



given in his key to adults (Ji-1, p. lJf6) , i. e., "abdomen with side- 

 spots and dorsal stripe concolorous," as this frequently is the case 

 with A. sollicitans. Alan Stone (personal communication, 1937) 

 stated, after examination of the specimen, that he believed it to be 

 incorrectly determined. 



AEDES DORSALIS (Meig.) 



Aedes dorsalis was reported from Delta, La., by Howard, Dyar, 

 and Knab (68), but the record is questionable, as the collection date 

 was 1904 and the species has not been reported since from that 

 locality. The specimen has now been lost. Beyer's identification 

 (12) of the species from Lake Charles, La., needs confirmation. This 

 species is abundant and widely distributed in the Western and North- 

 western States, and is said to breed in either salt or fresh water. 



Genus PSOROPHORA Robineau-Desvoidy 



(Syn., Janthinosoma L.-Arr., Grabhamia Theob.) 



To this genus belong some of our larger and showier mosquitoes. 

 Most of them are severe biters, but at the present time none are 

 known to carry disease, although one species (Psorophora columbiae) 

 appears in such swarms in southern Florida as to cause the death of 

 livestock by its mass attacks. The breeding habits of the group are 

 similar to those of the typical Aedes, to which they are closely re- 

 lated. The eggs ars adapted to withstand drying and may lie dor- 

 mant on the ground for long periods. They hatch upon being 

 flooded, and the larvae may complete their development in transient 

 pools, as they develop very rapidly. The larvae of two of the spe- 

 cies (subgenus Psorophora) are predacious upon other mosquito lar- 

 vae and are therefore of some benefit to mankind. The females of 

 these two species, the familiar gallinippers, offset the benefit to some 

 extent, however, as they are themselves avid bloodsuckers. 



The species of this genus are divided into three subgenera as 

 follows: (Psorophora) ciliat a and how ardii; (Grabhamia) columbiae, 

 discolor, pygmaea, and signipennis; (Janthinosoma) ferox, varipes, 

 cyanescens, and horrida. 



PSOROPHORA COLUMBIAE (D. and K.) 



(Syn., Janthinosoma floridense D. and K., and Oulex jamaicensis Dyar (not Theob.), in 

 part ; the Florida glades mosquito) 



The Florida glades mosquito breeds in temporary pools of rain 

 water and occurs commonly throughout the Southeast. It is most 

 abundant in the Florida Everglades, where it occasionally appears 

 in enormous swarms and has caused large losses of livestock by its 

 attacks (IS). During these outbreaks it is almost impossible for 

 humans to remain out of doors at night or in sheltered places during 

 the day without some protection. Workers in sugarcane fields some- 

 times protect themselves by means of smudge pots, and large smudges 

 are employed for the relief of stock. The problem in the Florida 

 Everglades has not been thoroughly investigated, and the possibilities 

 of control have not been determined, although breeding would appear 

 to be too widespread to offer much encouragement to any efforts in 

 this direction. The species also develops abundantly from grassy 



109619—39 i 



