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fighting this insect is by the destruction of it in the webs. This 

 can be easily done by means of a torch attached to the end of a 

 long pole. Care should be taken to do this when the insects are 

 in the web, and not while they are scattered over the tree feeding. 

 Ordinarily the best time will be early in the morning, or late in 

 the afternoon, or during a stormy day. This work should also be 

 done early in the season very soon after the appearance of the 

 leaves ; in fact as soon as the webs can be seen. It is a good deal 

 like locking the stable after the horse is stolen, to delay the des- 

 truction of these insects until they are nearly or quite fully grown, 

 as is usually done, if done at all. The caterpillars reach maturity 

 about the middle of June. A single mature caterpillar is repre- 

 sented ate, in the figure. At this time they leave the trees in 

 search of a place in which to spin their cocoons ; they may then 

 be seen crawling in all directions upon fences and over the 

 ground. They choose some secluded place as the lower side of a 

 stone or other object, where each makes for itself a dense silken 

 cocoon. Two of these cocoons are represented attached to a 

 piece of wood at b, in the figure. These cocoons may be easily 

 recognized by their having a yellowish white powder mixed with 

 the silk. 



Within the cocoon the insect changes to a pupa, and remains 

 in this state about three weeks ; it then emerges as a brownish 

 moth whose wings are crossed by two oblique whitish lines. This 

 moth is represented at a, in the figure. Soon after the adults ap- 

 pear the females lay their eggs, thus completing the circle of 

 transformations. 



There remains to be mentioned one other method of fighting 

 this insect ; that is by spraying the trees, as soon as the leaves 

 appear, with Paris-green water. In this way the caterpillars will 

 be poisoned while feeding upon the leaves. If the Apple-tree 

 Tent-caterpillar is the only insect to be fought in the orchard, I 

 do not think the spraying of the trees will be found as cheap a 

 method as the destruction of the webs, except in those cases where 

 the insect is very abundant. Ordinarily there will not be more 

 than one or two webs upon a tree ; and those can be destroyed 

 much more quickly and cheaply than the tree can be sprayed. 

 But if the trees are to be sprayed for the Codlinnioth or the 

 Canker-worm, the same application will serve to destroy the Tent- 

 caterpillar. 



JOHN HENRY COMSTOCK. 



