Bui. 329, U. S. Dept. of Agriculture. 
Plate II. 
Male Genitalia of Simulium. 
Fig 1 —Genitalia of male Simulium pictipcs: c, c, Claspers; a, a, a, anal plates; am, am, 
arms; 6, 6, basal pieces; st, st, styli; ad, adminiculum. Fig. 2.— Genitalia of male 
Simulium venustum. Fig. 3.— Genitalia of male Simulium jenningn. Fig. 4.— Geni- 
talia of male Simulium bracteatum. Fig. 5.— Genitalia ot male bimuhum vittatum. 
All greatly enlarged. (Original.) 
