(E) 

 EXPLANATIONS OF PLATES. 



Plate I. 

 Cecidomyia betulae. 



The Birch-seed Midge. 

 Fig. I. — Birch seeds : a, showing cavity from which the insect emerged ; 



b, galled seed showing window-like spot; c, ditto with two 



window-like spots; d, normal seed (x 2). 

 Fig. 2. — Lateral aspect of female midge, greatly enlarged. 



Fig. 3. — Tip of male antenna, very greatly enlarged. 



Fig. 4. — Ditto of female. 



Fig. 5. — Ventral aspect of empodium and claws of tarsus, very greatly 



enlarged. 

 Fig. 6. — Lateral aspect of last tarsal segment, very greatly enlarged. 

 Fig. 7. — Dorsal aspect of male genitalia, very greatly enlarged. 



Plate II. 

 Diplosis cucumeris. 



The Melon-vine Midge. 



Fig. I. — Lateral aspect of female, greatly enlarged. 



Fig. 2. — Antenna of male; drawn to same scale as the preceding. 



Fig. 3. — Two segments of female antenna, very greatly enlarged. 



Fig. 4. — A single segment of male antenna drawn to the same scale as 

 the preceding ; a, b, portions of dorsal setae ; c, d^ portions 

 of dorsal arched filaments; e,f,g, arched filaments. 



Fig. 5. — Tip of last tarsal segment, very greatly enlarged. 



Fig. 6. — Penis very greatly enlarged. 



Fig. 7. — Dorsal aspect of terminal abdominal segment of male show- 

 ing the large claspers crossed and the tip of the intromit- 

 tent organ, very greatly enlarged. 



