118 Psyche [December 
Key to the Genus Mochlonyx 
Adults 
1. Wing vestiture entirely pale yellow 2 
Wing vestiture black and yellow: cinctipes 
2. Scutellar setse numerous, arranged in two or three ir- 
regular rows : karnerensis 
Scutellar setse sparse, arranged in a single row : 
fuliginosus 
Larvae* 
1. Clypeal and frontal spines barbed from base to a little 
beyond middle : karnerensis 
These spines with long barbs beyond middle : cinctipes 
* The larva of M. fuliginosus is unknown. 
The following genera of the Chaoborinse are represented 
by single species: Corethrella brakeleyi Coquillett and Eu- 
corethra underwoodi Underwood. 
Subfamily Culicinae 
Key to Genera 
Adults 
1. Postnotum with a median tuft of setse located near the 
posterior margin (Fig. 2) : Wyeomyiu 
Postnotum without a tuft of setse 2 
2. Wings with the second marginal cell not half as long as 
its petiole (Fig. 5) : Uranotaenia 
Wings with the second marginal cell more than half as 
long as its petiole 8 
3. Scutellum rounded or crescent-shaped with an even 
fringe of marginal setse (Fig. 3) : Anopheles 
Scutellum distinctly trilobed (Fig. 4) with marginal 
setse aggregated on the lobes 4 
4. Spiracular bristles present (Fig. 2) 5 
Spiracular bristles absent 6 
5. Post-spiracular bristles present (Fig. 2) ; abdomen of 
female with the eighth segment wholly retractile : 
Psorophora 
Post-spiracular bristles absent; cross veins of wings 
