JANTHINOSOMA 547 



about twice as long as the segment, regularly tapered to a sharp tip, each with a 

 wavy central trachea. 



Egg (plate 146, fig. 671). Rather broadly fusiform, covered with regular 

 hexagonal reticulations, each with a stout spine from micropylar end, half as 

 long as the reticulation ; a square gelatinous cushion at micropyle. 



The larvas live in temporary puddles and feed upon the larvae of the non- 

 predaceous Psoivphora (Janthinosoma) and Aedes that accompany them. Du- 

 pree and Morgan state that larvae could always be found a few hours after a 

 heavy rain. Development is rapid and they observed pupation on the fourth day 

 of larval life. Dr. Dyar found them mixed with Psorophora ciliata in some cattle 

 tracks in the bottom of a nearly dried marsh at Tampa, Florida. The water was 

 almost gone and the larvje had become extremely concentrated. The eggs are 

 undoubtedly laid on the ground and the dry season is passed in this stage. We 

 have, however, no direct observations on these and other points in the life his- 

 tory. Mr. Taylor, in Cuba, writes : 



" We have collected the larvae in various months of the year, but only after a 

 very heavy rain, with a strong North wind. [The species] breeds in natural 

 collections of still water, preferably of medium depth, with or without vegeta- 

 tion. We usually collected them in pools that for at least a month previously 

 had been dried up. Always found other Culex larvae in conjunction with them, 

 principally C. [Psorophora] jamaicensis and C. confirmatus [Aedes scapularis]. 

 [The eggs] are quite large ; black ; oval in shape, both ends comparatively blunt, 

 one of them being truncated; both sides even and convex, the borders being 

 lined with short white spicules. They are laid singly on the surface of the water, 

 each mosquito depositing from 50 to 75 eggs. They are white when first laid, 

 but soon blacken with the action of the air. [The larvae] are very carnivorous 

 and cannibalistic, eating larvae of other species of mosquitos ravenously, also eat 

 small tadpoles. [The adult] bites readily every two days, sometimes every day. 

 The bite is not painful, and nothing is noticed at the time, but often after 24 

 hours, indurated areas occur, which may persist several days. Under natural 

 conditions we found the cycle of development to be more rapid than any other 

 Cuban mosquito. Eggs deposited during the night of Feb. 23rd produced mos- 

 quitos on the morning of March 2nd, making a minimum cycle from egg to 

 mosquito of 6 days for males, and 6| days for females, under natural con- 

 ditions." We think that the eggs are not normally laid upon the water, as stated 

 by Mr. Taylor. The observations of Dupree and Morgan, and of others, show 

 that the eggs are already upon the ground before the rain-puddles form. 



Southern Atlantic and Gulf States ; Cuba. 



Washington, District of Columbia, August 3, 1905 (T. Pergande) ; Piney 

 Point, Maryland, June 23, 1904 (T. Pergande) ; Hartsville, South Carolina, 

 July 23, 1901 (W. C. Coker) ; Natchez, Mississippi (Fleming) ; Belzona, Mis- 

 sissippi, July 4, 1904 (H. S. Barber) ; Scott, Arkansas (J. K. Thibault, Jr.) ; 

 New Orleans, Louisiana (J. W. Dupree) ; Tampa, Florida, March 18, 1905 (H. 

 Gr. Dyar) ; Havana, Cuba (J. R. Taylor) ; Havana, Cuba (C. F. Baker) ; San 

 Antonio de los Banos, Cuba (J. H. Pazos). 



Subgenus JANTHINOSOMA Lynch Arribalzaga. 



This group comprises two sections, one, Janthinosoma proper, with toothed 

 claws in the female, the other, to which the name Orahhamia properly applies, 

 with simple claws in the female. In Janthinosoma, the male genitalia have the 

 harpagones more strongly developed, more like Psorophora, than in Grabhamia, 

 although the division is not exact, since cyanescens has toothed claws in the 

 female, but the simpler type of genitalia in the male. In the larvae there is no 



