August, 1944 



Ross: Caddis Flies of Illinois 



239 



f 825 



PERSIMILIS 



OSTENl 



CINERASCENS 



827 



AVAR A 



828 



iilliii 



m 



'lill;ilMi 



EDOLESTONI 



IMMOBILIS 



832 



OCHRACEA 



Figs. 825-832. — Oecetis, female genitalia. All figures showing ventral aspect; in fig. 825 

 the sternites partially cut away to show bursa copulatrix. 



