54 ILLINOIS BIOLOGICAL MONOGRAPHS [54 



ff. Pi group on mesothorax and metathorax unisetose (Fig. 

 22). 

 g. Body without conspicuous gibbosities. NOCTUIDAE 

 gg. Body with one or more distinct transverse dorsal gib- 

 bosities; coloration mainly in transverse stripes. 



(AGARISTIDAE 



|NOCTUIDAE 



cc. Body bearing tufted or secondary setae or at least five setae on 



prolegs; mu usually associated with several other subprimaries 



(Figs. 59 to 68) ; crochets never arranged in a multiserial circle. 



d. Crochets uniordinal (Figs. 100, 105). 



e. Number of pairs of ventral prolegs three or six. 



f. Abdominal segments 2 to 7, inclusive, bearing prolegs, 

 those of segments 2 and 7 without crochets; verrucae 

 bearing large numbers of fine setae. 



MEGALOPYGIDAE 

 ff . Abdominal segments 2, 3 and 7 not bearing prolegs ; ver- 

 rucae bearing few setae. NOLIDAE 

 ee. Number of pairs of ventral prolegs four. 



f. Verrucae reduced, or obscured by development of secon- 

 dary setae, or absent, 

 g. Head muricate ; ocelli on papillae, the third very large. 



AGAPETIDAE 

 gg. Head smooth or nearly so; ocelli sessile, the third 

 normal, 

 h. Body very small, hemispherical in shape ; head re- 

 tractile, minute ; habit parasitic ; crochets uniordinal, 

 arranged in a complete circle. EPIPYROPIDAE 

 hh. Body cylindrical ; habits not parasitic. 



i. Secondary setae numerous, often obscuring both 

 primary setae and verrucae. 

 j. Spiracles small, circular (Fig. 104) ; ventral pro- 

 legs long, slender (Fig. 95). 



PTEROPHORIDAE 



jj. Spiracles elliptical, well developed (Fig. 79) ; 



ventral prolegs short (Fig. 105). 



k. Notch of labrum deep, with parallel sides and 



rounded bottom (see footnote, p. — ) ; body 



often bearing tufts and pencils of setae but 



never with cornicula. NOCTUIDAE 



kk. Notch of labrum acute, not with parallel sides ; 



body never bearing tufts and pencils of 



