Dististyle wider and fairly sharply curved; subapical 

 lobe, c, with upper stalk stout, leaflet very large 



and with irregular outline ( Fig. 110/4) 



peccator 



3. Middle phallosomal plate, m, armed with a cluster 



of stout sclerotized teeth ( Fig. 108B, 109B) 4 



Middle phallosomal plate, m, not toothed ( Fig, 10.^B- 

 107B) 5 



4. Lateral arm of inner phallosomal plate, n, with apical 



half expanded; middle plate, w, with ba.sal projec- 

 tion, a, curved back and up under teeth ( Fig. 108B ) 

 and without a ventral blade paralleling inner plate 



salinarius 



Lateral arm of inner phallosomal plate, «, narrow and 



II2C 



IMPATIENS 



II5B 



MINNESOTAE 



II6B 



MELANURA 



I'lG. 112- 1 Id. — Ciiliscta. male genitalia: A. j;enital capsule, 

 ventral aspect; B, phallosomc, dorsal aspect; C. lobe of tenth 

 sternite, lateral aspect. 



bladelike, apex cun,'ed laterad and paralleled by a 

 ventral blade of middle plate, m\ middle plate with 

 basal projection, a, projecting only laterad (Fig. 

 109B) tarsaiis 



5. Inner and middle phallosomal plates not separate from 



each other, together represented by a single structure, 



m (Fig, 103B, 107B; 6 



Inner phallosomal plate, «, forming a V- or U-shaped 

 structure; middle phallosomal plate, m, well devel- 

 oped, each arm terminating in a sickle-shajDcd proc- 

 ess, h (Fig, 105B, 106B) 7 



6. Middle phallosomal plate, m. with apexes forming a 



pair of stout rods curved laterally at their tips ( Fig, 

 I07B}; brush of tenth sternite, i. bushy. . .restuans 

 Middle phallosomal plate, m, with apexes forming a 

 pair of round serra'e lobes, the two forming a sclero- 

 tized oval; brush of tenth sternite, s, comblike (Fig. 

 1 03B ) territans* 



7. Rods of inner phallosomal plate, n, divergent, together 



forming a V-shaped structure ( Fig. 105B) 



pipiens 



Rods of inner phallosomal plate, n, convergent, togeth- 

 er forming a U-shaped structure ( Fig. 106B ) 



quinquefasciatus 



Key fo Species of CULISETA (Males) 



1. Phallosome consisting of a pair of long slender black 



rods tipped with a small membranous piece ( Fig. 



1I4B ) inornata 



Phallosome wide and bulbous and only lightly sclero- 

 tized (Fig. 113B. 116B) 2 



2. Phallosome somewhat quadrate, its lateral margins 



angulate near apex (Fig. 115B) minnesotae 



Phallosome ovate, its lateral margins sinuate or rounded 

 (Fig. 113B, 116B) 3 



3. Phallosome rather 8-shaped, the basal swelling at least 



as broad as the apical one ( Fig. 1 1 3B ) ; large in- 

 dividuals morsitans 



Phallosome broadly oval, broadest just before apex 

 (Fig. 116); small indi\iduals melanura 



Key to Species of ORTHOPODOMYIA (Males) 



Two species of this genus, jlhj and sigtiijerj. have been 

 found in Illinois, but the two species can be identified 

 to date only in the larval stage. They are rarely collected 



in light traps. Neither bites man. 



Key to Species of PSOROPHORA (Males) 



1. Dististyle with a large mcsal lobe and a long mcsal 



spurlike projection (Fig. 118) howardi 



Dististyle without mesal processes 2 



2. Dististyle with tip truncate; apical spur situated be- 



fore apex (Fig. 120) varipes 



Dististyle with tip round or tapered and small; apical 

 spur situated at end (Fig. 119) 3 



• Formerly listed as Culcx apicalis .-XdnniEi. a western species 

 ill whioli the arms of tlie phallosome are not joined by an apical 

 bridge (Fig. 104B), as is the case in Culcx tcrritnns (Fip. 103B1. 



24 



