August, 1944 



Ross: Caddis Flies of Illinois 



25 



membranous ones which contain de- 

 veloping genitalic parts, figs. 42, 43 2 

 Apex of abdomen with definite, pro- 

 jecting, platelike processes, figs. 

 570, 571, or finger-like or triangular 

 processes in addition to lobes con- 

 taining developing parts of genitalia, 

 figs. 20, 49-54 4 



Mandibles without teeth or serrations, 

 fig. 44 Hydroptilidae, p. 117 



Mandibles with either serrations, fig. 

 97, or distinct teeth, fig. 158 3 



Mandibles with teeth grouped near 



apex, figs. 158-161 



Philopotamidae, p. 44 



Mandibles with teeth near middle, or 

 mandibles only serrate, figs. 97-100 

 Rhyacophilidae, p. 30 



Fifth tergite with only anterior pair 

 of hook-bearing plates, third or 

 fourth tergites with both anterior 



and posterior pairs, figs. 40, 41 ... . 



Hydropsychidae, p. 76 



Fifth tergite with both anterior and 

 posterior hook-bearing plates, third 

 and fourth tergites at most with 

 anterior pair, fig. 20 5 



5. Seventh abdominal tergite without a 



pair ot sclerotized plates 6 



Seventh abdominal tergite with a pair 

 of sclerotized hook-bearing plates, 

 fig. 20 9 



6. Apical processes of abdomen short, 



appearing triangular from dorsal 

 view, sharply curved ventrad from 

 lateral view, fig. 45. . .Beraeidae, p. 208 

 Apical processes of abdomen either 

 much longer, fig. 49, or not curved 

 ventrad 7 



7. First abdominal tergite with a short, 



arcuate ledge near middle of seg- 

 ment, fig. 46; sclerotized plates of 



Fig. 49. — Helicopsyche borealis pupa, apical 

 processes, dorsal aspect. 



Fig. 50. — Lepidostoma liba pupa, apical 

 processes, dorsal aspect. 



Fig. 51. — Psilotreta sp. pupa, apical proc- 

 esses, dorsal aspect. 



Fig. 52. — Sericostoma sp. pupa, apical proc- 

 esses, lateral aspect. (After Ulmer.) 



Fig. 53. — Goera sp. pupa, apical processes, 

 dorsal aspect. (After Ulmer.) 



Fig. 54. — Limnephilus submonilifer pupa, 

 apical processes, dorsal aspect. 



