May, 1953 Burks: THe Mayrties or ILLINOIS 
105 
241 
QUEBECENSIS 
ats ae ae 
> 
RAPIDUS 
TYPICUS 
MARSHALLI ALTERNATUS 
Fig. 2+1.—Siphlonurus alternatus, head of 
Fig. 244.—Siphlonurus typicus, male geni- 
adult male, lateral aspect. talia. 
Fig. 242. — Siphloxurus quebecensis, male Fig. 245.—Siphlonurus marshalli, male geni- 
genitalia. talia. 
Fig. 243.—Siphlonurus rapidus, male geni- Fig. 246.—Siphlonurus alternatus, male geni- 
talia. talia. 
