20 STATE POMOLOaiCAL SOCIETY. 



June and the first of July. These insects remain in this state 

 about fifteen days, when the perfect insect or moth comes out, the 

 sexes pair, atid the females lay their eggs, about 400 in number, 

 in bolts around the twigs of the trees, in the same manner as the 

 common tent caterpillar. The egg masses may be distinguished 

 from those of the common tent caterpillar by their forming a com- 

 plete cylinder around the twig, and holding its full size from one 

 end to the other, appearing, as Riley says, of a uniform diameter 

 and docked off squarely at each end, while the egg masses of the 

 other are oval rings rounded at each end. The eggs remain on the 

 twigs during the fall and winter, and hatch out from the first to 

 the middle of May, when the young larvae go on their foraging 

 expeditions up to the time when they are fully grown, when they 

 wander off iti every direction seeking some place of concealment, 

 where they spin their cocoons, which differ somewhat from those 

 of the common tent caterpillars, in having a loose silken covering 

 outside of the oval cocoon. They do not always form this outside 

 loose covering, in which case thej' very closely resemble the 

 cocoons of the common tent caterpillar. I can find no evidence 

 that there is more than one brood of these insects in a year, but 

 every proof that they are one brooded. I have been collecting night 

 fl^'ing moths for some time, both at light and at sugar, and those 

 insects which are known to be one, two or several brooded, appear 

 and have been captured at one, or at several times during the sea- 

 €on, according as there is one or more broods, but I have never 

 ■ captured the moth of a forest tent caterpillar except at the time 

 corresponding to that when they came out of the cocoons in con- 

 finement, and I believe this is the experience of entomologists 

 who have collected the night flying moths for a series of years. 

 We must conclude, then, that when they are found in a tree after 

 •the egg masses have all been removed, and the tree once cleared 

 of the caterpillars, they have left some other tree which they have 

 stripped, and ascended the one in question by means of the trunk, 

 which they have frequently been observed to do. This may easily 

 be prevented by putting tar or printer's ink in a belt around the 

 •trunk of the tree. 



The habits of this insect in the larval state are considerably dif- 

 ferent from those of the apple tree tent-caterpillar, in this, that 

 while they spin a silken thread the same as the other, they do not 

 form a tent between the branches, since they do not rest in that 

 place, but upon the smooth side of the trunk or branch, and thus 



