INSECTS 213 



clothes moth. The eggs are laid on corn and the small grains. 

 The larva eats its way into the kernels, and emerges only 

 when it has transformed to the adult stage. When these 

 insects are in great numbers they do much damage. 



Stored grain may be treated by evaporating a dish of 

 bisulphide of carbon on top of the bin of grain. The fumes 

 settle into the crevices and kill the insects (see Appendix). 

 The bins should be made as close or air-tight as possible 

 during this treatment. Corn in open cribs is seldom troubled 

 with grain moths, except in warm climates, as the cold of 

 winter checks their breeding. 



Chinch Bug. — This is a showy insect, in spite of the fact 

 that it is less than one-fifth of an inch long, the body being 

 nearly black and the wings white. The chinch bug is a true 

 bug, with a sucking mouth, and has a continuous growing 

 stage from the egg to the adult form. The insects attack 

 wheat, com, and other grains and grasses, sucking the sap 

 and often destroying the crop or reducing the yield. It lives 

 over ^vinter in the adult stage. A single female can lay sev- 

 eral hundred eggs which soon hatch and the numbers become 

 very great by midsummer. After a wheat crop is killed or 

 has ripened they hunt for other succulent crops, such as corn. 

 As only the adults can fly, the greatest numbers have to 

 migrate to the next field by crawling. Efforts have been 

 successfully made to stop their march from one field to 

 another by plowing deep fiu-rows in which tar, kerosene, or 

 other materials may be used to destroy the insects. It is 

 also well to practise rotation of crops, and to plow the fields 

 in fall in places where the chinch bugs are abundant. 



Potato Beetles. — The Colorado, or ten-lined, potato 

 beetle is known well by all who raise potatoes (Fig. 131). 

 It passes the winter in the pupa stage, and the adult, appear- 

 ing in spring, lays clusters of yellow eggs on the under side 

 of potato leaves early in the season. These hatch into small, 

 soft, red grubs which eat the leaves. The best remedies 



