August. 1944 



Ross: Caddis Flies of Illinois 



211 



1723/] 



724 



725 



726 



Anal Appendages of Pupae 



Fig. 721. — Leptocerus americamis. 



Fig. 722. — Athripsodes tarsi-punctatus. 



Fig. 723. — Oecetis inconspicna. 



Fig. 724. — Triaenodes tarda. 



Fig. 725. — Mystacides sepulchralis. 



Fig. 726. — Leptocella sp. 



Mandibles of Pupae 



Fig. 727. — Leptocerus americanus. 



Fig. 728. — Triaenodes tarda. 



Fig. 729. — Oecetis inconspicua. 



Fig. 730. — Athripsodes tarsi-punctatus. 



Fig. 731. — Mystacides sepulchralis. 



Fig. 732. — Leptocella sp. 



Anal appendages with the base nar- 

 row; shoulder, if present, situated 

 at the middle, fig. 722 2 



2. Mandibles with a definite area of teeth 



below the apical point, fig. 730; fre- 

 quently stocky and triangular 3 



Mandibles without teeth, sometimes 

 with the apex minutely serrate, fig. 

 731; always with blade very narrow 5 



3. Anal appendages slender, straight and 



of uniform thickness throughout, 



fig. 723 Oecetis, p. 236 



Anal appendages with a distinct 

 shoulder at or near middle, beyond 

 which the apex tapers evenly to a 

 sharp point, fig. 722 4 



4. Mandibles with apex long and slightly 



twisted, teeth small and situated on 



a slight convex bulge, fig. 728 



Triaenodes, p. 244 



Mandibles with apex shorter and 

 straight, either the teeth situated 

 within an angulation or curve, fig. 

 730, or mandible short and triangu- 

 lar Athripsodes, p. 221 



5. Mandibles with a large, bulbous base, 



the apical blade minutely serrate and 

 little longer than base, fig. 731. . . . 



Mystacides, p. 253 



Mandibles with base small, blade long 

 and slender, not serrate, fig. 732. . . 

 Leptocella, p. 213 



Adults 



1. Front wings with stem of M atrophied, 

 leaving only two main veins between 

 convex Ri and convex Cui, fig. 733 



Triaenodes, p. 244 



Front wings with stem of M present, 

 so that three main veins are present 



Fig. 733. — Triaenodes injusta, front wing. 



Fig. 734. — Oecetis inconspicua, front wing. 



Fig. 735. — Mystacides sepulchralis, front 



wing. 



