<i7 



The various species of grasshoi)])ers injurious to corn in lliiaois are 

 so similar in their habits and life history that it is not necessary for any 

 l^ractical purjxjse to distinguish them, but all may be treated/so far as 

 the corn crop is concerned, as a single economic group. It may be of 

 some interest to know, however, that the most abundant species in corn 

 is the red-legged grasshopper (Melanoplus femur-ruhrum, Fig. 35), 

 everywhere the commonest of its family hi this state. With it is ordi- 

 narily associated the heavier and more sluggish olive grasshopper (M. 

 cliff erentialis, Fig. 36), with a sprinkling of the two-striped grasshopper 

 {M. hivittatus, Fig. 37). In the southern part of the state the lesser 

 migratory locust {M. atlanis) and the large conspicuous bird grasshopper 

 (Schistocerca americana, Fig. 38) also become. abundant, and, like the 

 species femur-ruhrum, sometimes collect in considerable swarms and 

 make short flights across the country. 



THE EAR-WORM OR CORX-WORM. 



Heliotliis armigcr Hiiljn. 

 (Plate IV.) 



This insect, known also as the cotton bol!-worm, the tobacco bud- 

 worm, the tomato-worm, etc., is a slender, nearly hairless caterpillar 

 (see PI. IV), an inch and a half to two inches long, varying in color 

 from light green to brown, and marked with alternating light and dark 

 stripes and lines running lengthwise of the body. A common type has 

 a dark-broAMi stripe down the middle of the back, with a fine white line 

 in its center, and bordered on each side by a pale brown stripe, and 

 below the latter a distinct whitish stigmatal strii^e. Inconspicuous 

 shining tubercles, each bearing a delicate hair, are arranged in transverse 

 rows on each segment of the bod>-. The head is amber-yellow, and the 

 legs are dark. 



As an ear-worm this caterpillar feeds on the com beneath the husk, 

 from the time the ear is formed until after it is thoroughly ripe, and it 

 also eats the husk, the leaf, the tassel, and the tender stalk. Although 

 it probably prefers corn to any other of its food plants, it is likewise fond 

 of cotton, tobacco, beans, and the fruit of the tomato, and feeds freely 

 upon a great variety of other plants, including pumpkin, squash, peaiuit, 

 pea, cow-pea, hairy vetch, pepper, okra, jimson-weed (Datura), nnpam- 

 gus, ground-cherry, hemp, morning-glory, gladiolus, mallow, mignonette, 

 gerannun, sunflower, poppy, and peach. It sometimes de^'ours soft- 

 bodied insects, such as the cabbage-worm and cotton-worm, and has 

 been known to eat the young of its own kind even when vegetable food 

 was plentiful. As a bean insect its injuries in the South are of the most 

 serious charactei-, whole crops being destroyed, and it is also one of the 

 standing and most destructive pests of cotton and tobacco. In the 



