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THE CORN-WORM, OR BOLL-WORM. 



By Peof. G. H. Fkench. 



{Heliothis armegera, Hub.) 



Most of the insects that come before the economic entomologist 

 for consideration are comparatively local in their depredations, 

 though a few are found over a large area. The Chinch-bug, so 

 dreaded by the farmers of the Mississippi Valley, is almost unknown, 

 except by name, to those of the eastern and central States ; the 

 Rocky Mountain Locust is dreaded only in a belt west of the Mis- 

 sissippi river. The Cotton- worm (Aletice) is of necessity confined to 

 the cotton-producing States, and so on. On the other hand, the 

 Colorado Potato Beetle may travel wherever the tuber is grown ; the 

 Cabbage-worm (Pieris Rapes) seems inclined to spread over the whole 

 United States, and the same may be said of a few others. The 

 caterpiller now under consideration in a measure belongs to the lat- 

 ter class of insects. It has been found not only in various parts of 

 our dominion, but in parts of the other continents. An insect, ta 

 enjoy such a wide range, must either feed upon a diversity of food, 

 or upon some plant that is susceptible of cultivation under varying 

 climatic situations — from the cold of Canada to the almost tropical 

 heat of the Gulf States. Both of these may be said of the Corn- 

 worm. As corn, in some of its varieties, may be cultivated in all 

 portions of the Union, this plant may serve as food for this cater- 

 pillar; and it may be classed, wherever corn is raised, as an inju- 

 rious insect upon that plant. But while this is true, the varied 

 food habit of this insect is such that it feeds readily upon cotton in 

 the Southern States ; on tomatoes in the Central States, where that 

 crop is almost a staple ; and it has been found in various localities 

 feeding on green beans and peas, upon the stem of the garden 

 Gladiolus, and upon pumpkins. In Europe the list is increased by 

 the addition of the heads of hemp and the leaves of tobacco and 

 lucerne. In my article on this insect, in the Seventh Illinois Report 

 of the State Entomologist, occurs this statement; "If I mistake 

 not, I have found the same worm in the growing seed pod of a 

 species of Hibiscus {H. Grandiflorci' that grows along our streams." 

 Lately I have examined pods of this plant sent me from Grand 

 Tower, 111., by Mr. John Marten, and I find the caterpillar within 

 them resembling, in size and some of its markings, a third-grown 

 Corn-worm, but in reality it is a Pyralid larva, related, I should 



