ILLUSTRATIONS 
Page. 
Map showing distribution of Hessian fly in America Frontispiece. 
Plate I. Wheat plant showing injuries by Hessian fly; also stages in devel- 
opment of the insect 58 
II. Different views of Hessian fly at different stages; also parts 
enlarged 58 
Fig. 1. Cecidomyia destructor; genitalia 15 
2. Merisus destructor 31 
3. Bteotomus subapterus 32 
4. Eupelmus allynii, male 34 
5. Eupelmus allynii, female 34 
6. Platygaster herrickii 35 
7. Tetrastichus productus 37 
8. Entedon epigonus 40 
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