THIRD ANNUAL REPORT OF STATE ENTOMOLOGIST. 219 



THE CORN WORM. 



Hdiothis armigcr liubn. 



This well known insect came prominently before the people 

 of Montana in the season of 1905 as a pest of corn. Simultaneously 

 throughout the state, it appeared in great numbers about the mid- 

 dle of iVugust, eating within the ears of both sweet and field corn. 

 The writer made a personal examination in the corn fields of limited 

 extent in the vicinity of Uillings and found that about 90 per cent 

 of the ears were more or less injured. 



This is a species which in the cotton belt of the country is known 

 under the name of the "Cotton Boll worm". As such it has a record 

 of enormous destructiveness to cotton caused by the larvae eating 

 into the bolls of cotton in a manner similar to the way they attack 

 corn ears. Entering a bud or boll through the hole eaten through 

 the surface, the caterpillar feeds on the internal parts killing the 

 bud and causing it to fall. 



In the southern portion of the United States it feeds also on 

 corn but is of less prominence in tliis role because of the less im- 

 portance of the corn crop. 



GEOGRAPHICAL RANGE. 



Among moths this in one of the most widely distributed spec- 

 ies known, for it occurs in all parts of the world, being well known 

 in Great Britian and other old world countries and having been re- 

 corded from both South and North America and the Orient, the 

 East Indies, Patagonia, the Cape de Verde Islands, Africa and 

 Australia. Its presence within its climatic range, anywhere on 

 earth, need not cause suri^-isc. 



OTHER FOOD PLANTS. 



Besides feeding on cotton and corn, it has been known less promi- 

 nently as a destroyer of tomatoes, boring into both the fruit and the 

 stems. It eats into pea and bean-pods and burrows into peppers, 

 pumpkins and squashes. To some extent it feeds on various other 

 plants, as chick-pea, leaves of hemp, leaves and buds of tobacco, 

 leaves of alfalfa, henbane, strawberry and others. A complete list 



