100 



ILLINOIS BIOLOGICAL MONOGRAPHS 



[270 



EXPLANATION OF PLATE 

 Labium 



Chloropisca glabra, caudal aspect. 



CJiloropisca glabra, cephalic aspect. 



Dolichoptis bifractus, mesal aspect. 



Dolichopus bifractus, caudal aspect. 



Dolichopus bifractus, lateral aspect. 



Pipunculus cingulatus, caudal aspect. 



Pipunculus cingulatus, cephalic aspect. 



Borborus equinus, caudal aspect. 



Borborus equinus, mesal aspect. 



Sepsis violacea, caudal aspect. 



Sepsis violacea, mesal aspect. 



Eristalis tenax, mesal aspect. 



Eristalis tenax, caudal view. 



Eristalis tenax, distal end of theca, caudal aspect. 



Ochthera mantis, caudal aspect. 



Ochthera mantis, mesal aspect. 



Calobata univitta, mesal aspect. 



Calobata univitta, caudal aspect. 



Coelopa vanduzeii, caudal aspect. 



Coclopa vanduzeii, mesal aspect. 



Sphyracephala brevicornis, caudal aspect. 



Sphyracephala brevicornis, mesal aspect. 



Occothca fenestralisf caudal aspect. 



Oecothea fenestralis, mesal aspect. 



Drosophila anipclophila, caudal aspect. 



Drosophila ampelophila, mesal aspect. 



Chrysomyza demandata, mesal aspect. 



Chrysomyza demandata, caudal aspect. 



Siphona geniculata, distal end, cephalic aspect. 



