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PAPERS ON CEREAL AND FORAGE INSECTS. 



in Plate I were collected in Kansas and forwarded, in moist paper, 

 to Washington, D. C.. and photographed by the official photographer, 

 Mr. L. S. Williams, and show the injuries more clearly, while Plate 

 II, photographed in the field, illustrates the effect on the standing 

 corn. Small plants, even those of less than one-half inch in diameter, 

 are often recipients of eggs from which the larvae, on hatching, bur- 

 row into the heart of the plant and cut off the growing bud, thus 

 killing the top ; they then direct the burrowing downward only to 



Fig. 7. — Corn plant showing result of 

 attack by the maize billbug : a. Larval 

 burrow containing pupa in natural 

 position : 6, egg puncture containing 

 eggs, a, Reduced two-thirds ; b, en- 

 larged. (Original.) 



Fig. 8. — Swamp grass (Tripsacum 

 dactyloicles), attacked by the 

 maize billbug. Reduced two- 

 thirds. (Original.) 



devour the stub, leaving themselves without food, and, being footless 

 grubs, they of course perish. Plants of more than one-half inch 

 diameter which become infested with larva? make very poor growth, 

 being very slender, rarely reaching a height of more than 2 or 3 feet 

 before tasseling (PL II), and do not produce shoots or ears. These 

 that do not become infested until they are half grown may produce 

 small ears. Each larva inhabits only the one burrow, and if, owing 

 to any mishap, it becomes dislodged from it. it is powerless to rees- 

 tablish itself. The larva does not become dislodged from the burrow 



