50 ILLINOIS BIOLOGICAL MONOGRAPHS [SO 



bb. Prolegs always present, when reduced represented by at least 

 rudimentary crochets, 

 c. Body bearing neither tufted nor secondary setae ; prolegs not 

 bearing more than four setae (pi, nu, tau, and sigma) (Pig. 

 101), except that there may be five when crochets are arranged 

 in a multiserial circle ; mu never a verruca, never associated with 

 additional subprimaries. 

 d. Crochets never arranged in a pseudocircle (Fig. 97) or meso- 

 series (Fig. 105), usually in a circle (Fig. 101) or penellipse 

 (Fig. 98) or transverse bands (Fig. 99) ; epsilon on pro- 

 thorax always below alpha and gamma (Fig. 7). 

 e. Prolegs of sixth abdominal segment absent or without cro- 

 chets; larvae small, leaf -miners. GRACILARIIDAE 

 ee. Prolegs of sixth abdominal segment as well developed as 

 those of segments 3, 4, and 5. 

 f. Kappa group on prothorax bisetose, theta absent (Fig. 

 43) ; crochets never multiserial. 

 g. Crochets uniordinal, arranged in a complete circle ; body 

 cylindrical ; Pi group on mesothorax unisetose. 



ORNEODIDAE 

 gg. Crochets biordinal (Figs. 98, 101), except when body 

 is spindle-shaped and very fleshy and when Pi group on 

 mesothorax is bisetose (Fig. 50). PYRALIDIDAE 

 ff. Kappa group on prothorax trisetose, theta present (Fig. 

 39). 

 g. Crochets arranged in transverse bands (Fig. 99). 

 h. Crochets arranged either in a single transverse row or 

 in two mnltiserial bands on each proleg. 



INCURVARIIDAE 

 hh. Crochets always arranged in two uniserial bands on 

 each proleg. 

 i. Kappa and eta of abdomen remote. 



BUCCULATRIGIDAE 

 ii. Kappa and eta of abdomen adjacent (Fig. 41). 

 j. Crochets of anal prolegs in two groups. 



GELECHIIDAE 

 jj. Crochets of anal prolegs in a single transverse 

 row. 

 k. Front extending about one third of the distance 

 to the vertical triangle. COSSIDAE 



kk. Front extending at least two thirds of the dis- 

 tance to the vertical triangle. 



