274 FUNDAMENTALS OF AGRICULTURE. 



Importance of Knowing the Kind of Insect Causing 

 the Trouble. It is absolutely necessary to know what 

 kind of insect is causing the trouble, whether it is a 

 biting or a sucking one. So this is the first point to 

 determine. If the pest is a biting one, then some kind 

 of poison sprayed upon the plant will usually be the 

 best remedy. If the pest is a sucking one, then some- 

 thing must be used that will kill by contact. 



EXERCISE. Catch some grasshoppers and kill them by putting a 

 little chloroform along the sides of the body. Examine the mouth 

 of a grasshopper and find the two, hard, black jaws. Catch some 

 June-bugs and some potato beetles and see if these insects do not 

 have similar jaws. 



Find a squash-bug or harlequin cabbage-bug, and look on the 

 under side of the head and thorax for the long, slender beak. Ex- 

 amine other bugs for this beak. 



SECTION XLIII. THE BOLL WEEVIL. 



By PROF. WILMON NEWELL, 

 Texas State Entomologist. 



The boll weevil is the greatest enemy of the cotton 

 crop, for it rarely destroys less than one-third of the 

 cotton crop in fields where it occurs. Frequently the 

 damage amounts to one-half or three-fourths of the 

 crop, and sometimes all is destroyed. 



History of the Insect. Like many other of our most 

 injurious insects the boll weevil has come to us from an- 

 other country, for it is a native of Central America and 

 Cuba, where its ancestors have lived for centuries, sub- 

 sisting upon the wild " tree cotton " which grows in 

 the tropics. Cotton culture in Mexico and Central 

 America was not important until after the perfection of 

 the cotton gin, but gradually large areas were devoted 

 with profit to the production of the staple. When 

 cultivated cotton was first grown in localities where the 

 boll weevils existed, these insects found that the tender 

 squares were far preferable to those of the wild cotton, 

 and they quickly adapted themselves to the cultivated 



