88 



Illinois Natural History Survey Bulletin 



Vol. 23, Art. 1 



Aedeagus with a dorsal pair of small 

 hooks, figs. 359, 360 5 



5. Lateral arms of apex of aedeagus with 

 end containing a protrusible bundle 

 of pale but sclerotized spicules, fig. 



359 vexa, p. 97 



Lateral arms of apex of aedeagus with 

 end surmounted by a ring of short 

 setae but without a bundle of 

 spicules, fig. 360 piatrix, p. 97 



346 



350 



354 



347 



355 



6. Dorso-lateral arms of aedeagus with a 



conspicuous lateral spine before 

 apex and a bundle of spicules at 



apex, fig. 361 sparna, p. 97 



Dorso-lateral arms of aedeagus with 

 spine either absent or apical, fig. 

 362, or arms absent 7 



7. Main body of aedeagus sinuate, al- 



most Z-shaped, fig. 362 



slossonae, p, 99 



348 



352 



356 



349 



353 



357 



Hydropsyche Larvae, Head and Pronotum 



^•^' ??S'~^- '''■'■''• Fig. 352.—//. simulam. 



^•^' otl Phalerata. pig. 353.—//. hageni. 



V^' ?^n*~?- '^'^'^"'- FiS- 354.— //./mo«/. 



r>-?" ;cn'~^- ''^'■''^''- I'iS- 355.—//. -slossonae. 



r"-?" ?c?'~'^- '"''""• Fi^- 356.—//. bifida. 



l-ig. 351.—//. artnale. Fig. Zhl.—H. recurvata. 



