I 



216 MANUAL OF VEGETABLE-GARDEN INSECTS 



excrement left by the larva in its burrow under the husk serve 

 as an excellent medium for the growth of various molds and 

 bacteria, which greatly augment the injury inflicted by the 

 insect. As many as six larvte sometimes infest an ear but 

 usually only two or three are present, in spite of the fact that 

 normally a much larger number of eggs are deposited on each 



mass of silk. This is to be 

 accounted for by the can- 

 nibalistic habits of the 

 caterpillars. They feed 

 voraciously not only on 

 each other but on any other 

 caterpillars that come in 

 their way. 



Both field and sweet corn 

 are subject to attack but 

 the latter seems to be pre- 

 ferred by the insect. The 

 loss to field corn is not so 

 great because the uninjured 

 kernels can be used, but in 

 the case of sweet corn good 

 prices cannot be obtained 



Fig. ISf). — Two full-grown ear-worms for WOrmy ears. The pCSt 

 on the tip of an ear of field corn Jg ^j^^^^ destructive in the 

 (natural size). , „ , 



latter part oi the season, 

 owing to the greater number of moths in the later broods. 

 In the last crop of corn in the vicinity of New York, some- 

 times nearly every ear is infested, while the earlier plantings 

 may be practically free. In many parts of the South, it is 

 impossible to raise a clean crop of sweet corn because of 

 the depredations of this insect. When full-grown, the cater- 

 ])illar leaves the ear, usually by gnawing a round hole through 

 the husk, but in some cases it may escape at the tip. Some- 



