326 



MISSOURI AGRICULTURAL REPORT, 





trodticed in the form of corn-worms. These insects then start to decay, 

 and as soon as they are thoroughly under way the entire corn decays, ani 



what would otherwise have 

 been ensilage is ruined. My 

 observations lead me to be- 

 lieve that in every case of 

 failure to make ensilage the 

 cause can be traced directly 

 to the presence of large 

 quantities of these corn 

 worms in the corn at the time 

 it was cut up and placed in 

 the silo. 



The adult of the corn 

 worm is a greenish-yellow 

 moth, with a black spot in 



Fig. 64.-Corn AVorni, HelioiMs armiger ; a, b. the middle of the front wingS 

 Ifulti""'"''^ enlarged; c, larva; d, pupa; e, f, ^^^d with varioUS olivC mark- 

 ings across them. One of these moths is represented, natural size, in 

 figure 64, e, with its wings expanded, and at /, with its wings closed, rts 

 the insect appears when at rest. These moths deposit their eggs in various 

 situations, upon various plants upon which the larvae feed. They also 

 deposit their eggs in the silk of the corn, and occasionally upon the 

 leaves, and the larvae, when they hatch, may feed upon the leaves of the 

 corn plant, or upon the husks or the silk, but more frequently enter the 

 ear and feed upon the developing kernels of corn, where they mine down 

 towards the base of the ear, but, as a rule, do not reach the base, but 

 are contented with ruining the upper half of the ear. There may be 

 more than one of these larvae in an ear of corn, but in the great ma- 

 jority of cases only one larva is found. 



When these larvae become full grown they are from one and onc- 

 hjilf to two inches in length, of a pale green or dark brown color, with 

 dark stripes and with a yellow head. One is represented in figure 64. c. 

 When full grown larvae they leave the corn plant, or other plant upon 

 which they have been feeding, and enter the ground for an inch or two, 

 and then, by wriggling their bodies, pack the earth away so as to make 

 little earthen cells, line them with a little silk, and inside of these earthen 

 and silky cocoons transform to pupae, one of which is represented in its 

 cocoon in figure 64, d. There are in Missouri three broods of these 

 insects each year. The winter is passed as a pupa inside the cocoon under 

 ground. In the spring these pupae transform to adults, which fly about 



