ENEMIES OF THE AGRICULTURIST. 



313 



pests 



are 



often 



Mississippi watershed being specially subject to ravages 



of this mosquito-like pest, the attacks of which are so 



awful that cattle become terrified at the sounds made 



by these gnats, and to flee from the 



drowned. 



To Check Fungi 



and Insects. In the 



application of means 



for checking destruc- 



tive insect pests, it is 



well to note that they 



all obtain their food 



by sucking or biting ; 



sucking insects are 



provided with tube- 



like sucking mouths, 



by which they pene- 



trate the tissues and 



pump out the juicy 



contents. Biting in- 



sects have jaws, with Hand Sprayer at Work; 



which they bite and destroy the entire substance. It is 



evident then that an insect subsisting upon the liquids 



inside of a fruit, leaf, 

 or twig is not likely 

 to be killed by a 

 poison applied to the 

 outside of a leaf which 

 might kill an insect 

 eating the leaf; but 

 there is another way 

 of reaching them. 

 Insects do not breathe 

 as we do. They have, 

 instead of noses and 

 lungs, rows of very 



Spraying in the Orchard. *?. , . . 



small breathing open- 



ings along the sides of their bodies, with air tubes which 

 branch and spread out through all the tissues of the body, 

 carrying air to them. It is a fortunate circumstance that 



