864 MOSQUITOES OF NOETH AMEBICA 



scales from the occiput. This resemblance is made still more startling by the 

 occurrence, in those species which further agree in the simple claws of the 

 female (splendens and albomaculatus) , of minute bristles on the postnotum. 

 Mr. P. W. Edwards of the British Museum first informed us of the presence of 

 such bristles on the type of Tlwmagogus splendens. Examination of several 

 of our specimens failed to reveal bristles on the postnotimi, and this led us to 

 conclude that Williston's genus was distinct and belonged to the Sabethini. 

 Consequently we adopted the name Stegoconops for the forihs before us (see 

 volume ii of this work, pi. 33, figs. 162, 163, 164, pi. 24, fig. 165, pi. 77, pi. 136, 

 figs. 438 and 439). Subsequent careful examination of a series reared from 

 larvae showed that one, two or three minute bristles are usually present in the 

 two species above mentioned, although they are well back on the postnotum and 

 diflScult to detect. We are unable to accept the occurrence of these bristles as 

 an indication of close relationship between Hoemagogus and the Sabethini, but 

 incline rather to the view that the bristles have developed independently and 

 that the other resemblances are due to convergence. Certain it is that there is 

 no corresponding modification in the larval or genetalic structures of HcBma- 

 gogus, and that we must consider these as more fimdamental, because less sub- 

 ject to adaptational modifications. 



The species, fall into two well marked groups as indicated in our table of the 

 adults. These groups have been treated as separate genera by Lutz, CoquUlett 

 and Theobald ; but we consider their separation quite unnecessary. 



All the species are inhabitants of water in hollow trees and similar situations, 

 such as open bamboo- joints. It is probable that in suitable situations they will 

 occur in artificial wooden receptacles holding water. We have no information 

 concerning the egg-laying habits or the length of larval life, etc., although it is 

 probable that the eggs are laid singly on the sides of the receptacles containing 

 the water and that the length of larval life is considerable, as is the case with 

 the tree-hole inhabiting species of Aedes. We have no observations on the 

 mating habits of the adults. It is probable that there are two different styles 

 of copulation within the genus on account of the differences in claw structure 

 between the species. The adults inhabit forests or shady places. The females 

 suck blood. They are active during the daytime, as their brilliant colors would 

 lead one to infer. 



Tables of the Species, 

 adults, stbuctuee, and colobation. 



1. Second marginal cell longer than the second posterior cell; claws of female 



simple 2 



Second marginal cell shorter than the second posterior cell; claws of female 



toothed 3 



2. Abdomen without spots dorsally splendens Williston (p. 865) 



Abdomen with basal segmental silvery white spots 



alhomaculatus Theobald (p. 868) 



3. Abdomen with segmental basal silvery bands equinus Theobald (p. 871) 



Abdomen with silvery bands on the last two or three segments only 



capricornii Lutz (p. 875) 



ADULTS, MALE GENITALIA. 



1. Terminal filament of clasp with a short apical spine; no rounded knob at 



the base of the clasp 2 



Terminal filament of clasp with a long apical spine; a rounded setose knob 



at the base of the clasp within 3 



2. Harpago with a broad expanded filament aWomaculatus Theobald (p. 870) 



Harpago with a small narrow filament splendens Williston (p. 866) 



3. Harpago slender, elongate, with a small terminal filament; harpes long, 



slender, with a sharp point capricornii Lutz (p. 876) 



Harpago stout, greatly developed, spinous in the middle, with a large sub- 

 terminal expansion; harpes short, bluntly rounded 



equinus Theobald (p. 873) 



