SB 

 818 

 C578 

 ENT 



Circular No. 113. 



Issued November i:>, T.)09. 



United States Department of Agriculture, 



BUREAU OF ENTOMOLOGY, 

 L. O. HOWARD, Entomologist and Chief of Bureau. 



THE CHINCH BUG. 



(Blissus leucopterus Say.) 



By F. M. Webster, 

 In Charge of Cereal and Forage Insect Investigations. 



INTRODUCTION. 



Few insects, and certainly no other species of the natural order to 

 which this one belongs, have caused such enormous pecuniary losses 

 as has the chinch bug (Blissus leucopterus 

 Say) (fig. 1 ) . No other insect native to the 

 Western Hemisphere has spread its devastat- 

 ing hordes over a wider area of country (see 

 map, fig. 7) with more fatal effects to the 

 staple grains of North America than has this 

 one. But for the extreme susceptibility of 

 the very young to destruction by drenching 

 rains and to the less, though not insignificant, 

 fatal effect during rainy seasons of the para- 

 sitic fungus Sporotrichum glohuliferum Speg., 

 on both the adults and young, the practice of 

 raising grain year after year on the same 

 areas, as is followed in some parts of the 

 United States, would become altogether un- 

 profitable. Some of this insect's own habits, emphasizing as they do 

 the effects of meteorological conditions, arc among the most potent 

 influences that serve to hold it within bounds by giving its tendency 

 to excessive increase a decidedly spasmochc character 



9917-cir. 113-09 — 1 X;A\\soniaii 



Fig. 1.— Chinch bug (Blissus leu- 

 copterus): Adult of long-winged 

 form, much enlarged. (Author's 

 illustration.) 



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