162 ILLINOIS BIOLOGICAL MONOGRAPHS [lb2 



EXPLANATION OF PLATE 



Typical verruca of Arctiidae; Estigmene acraea. 



Drcpana harpagula, of Europe, Platypterygidae. Lateral aspect showing 

 anal process. 



Typical chalaza ; Utetheisa bclla, Arctiidae. 



Typical verricule ; Acronycta rubricoma. 



Typical fleshy filament; lateral aspect of Anosia plexippus, mesothorax. 



Nepiicula sp., Nepticulidae. Lateral aspect of the three thoracic and 

 first two abdominal segments showing the first three pairs of fleshy 

 legs, and their location. 



Adda degeerella, of Europe, Incurvariidae. Crochets. 



Plutella maculipcnnis, Yponomeutidae. Proleg, mesal aspect. 



Pseudanaphora arcanella, Acrolophidae. Ventral aspect of proleg. show- 

 ing crochets arranged in a multiserial circle. 



Drepana harpagula, Platypterygidae. Latero-ventral aspect of proleg, 

 showing crochets arranged in a pseudocircle. 



Psorosina hammondi, Pyraustinae, Pyralididae. Ventral aspect of pro- 

 leg, showing crochets arranged in a mesal penellipse. 



Sanninoidea exitiosa, Aegeriidae. Crochets arranged in transverse 

 bands. 



Estigmene acraea, Arctiidae. Mesal aspect of proleg; crochets heteroi- 

 deous, uniordinal, arranged in a mesoseries. 



Pyralis farinalis, Pyralidinae, Pyralididae. Crochets biordinal, arranged 

 in a complete circle. 



Lycaena coridon, Lycaenidae. Proleg, mesal aspect, showing interrupted 

 mesoseries and fleshy lobe. 



Ornix geminatella, Gracilariidae. Crochets of abdominal segment 3. 



Zygaena punctum, Zygaenidae, of Europe. Spiracle. 



Scolecocampa libuma, Noctuidae. Mesal aspect of proleg; crochets uni- 

 ordinal, arranged in a mesoseries ; also homoideous. 

 Fig. 106. Saturniidae. Mesal aspect of proleg; crochets biordinal, arranged in a 

 mesoseries. 



