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the leaves of various trees, having been found on the apple, cherry, 

 quince, oak, hickory, black walnut, black locust, birch, basswood, thorn, 

 hazel and sumach. The eggs, from seventy to a hundred in number, are 

 white and spherical, and are deposited in a dense patch, side hy side, on 

 the under side of the terminal leaves, so that the young worms have 

 the newest and tenderest foliage to feed ui)on. They eat at first only 

 the under side of the leaves, but as they increase in size they devour 

 the whole leaf except the mid-rib. They do not spin any visible web, 

 but are nevertheless strictly gregarious, feeding in dense clusters, and 

 eating clean every leaf as they go. When all the leaves upon one twig 

 or branch are consumed, they hastily migrate to another, sometimes 

 making their appearance upon a remote part of the tree. When not 

 feeding they often rest with their heads and tails ele\'ated at right 

 angles with the rest of their bodies, and they always suddenly throw 

 themselves into this attitude when they are disturbed. 



But what is calcidated more than anything else to attract attention to 

 these worms, is their remarkably gregarious habit at their moulting 

 periods. They then come down upon the side of the trunk, and mass 

 themselves together, very much after the fashion of a swarm of bees, 

 sometimes making a quantity as large as could be held in both hands 

 united. They maintain themselves in this position bj^ means of shreds 

 of web extending over and through them. Those which I have particu- 

 larly noticed remain in this i^osition two days and niglits. Before the 

 middle of the third day, those which have first accomplished their 

 moulting, begin to crawl up the tree, and by the close of the third day 

 nearly all have ascended. During this time they have cast off their 

 outgrown skins, which are left dry and empty, attached to the web. 

 They do not always come down upon the trunk to go through with this 

 operation, but are sometimes seen attached, en rnasse, to the under side 

 of the large horizontal branches. 



These worms, like the larvse of the fixll web-worm, and the tent cater- 

 pillar of the forest, and some other social caterpillars, become less gre- 

 garious towards the close of their larval career, and after the last moult 

 they often become quite solitary and erratic. They are one of the latest 

 of our insects, never making their al)l:^parance before mid-summer, and 

 being seen of different sizes from this time on, till the frost renders the 

 foliage no longer fit for their nutriment. 



As these insects all pass the winter in the pupa state, and are there- 

 fore in the same state of maturity when the summer opens, and as the 

 female moth lays her eggs all at one operation, the question may natur- 

 ally be asked how this succession of broods through the season is pro- 

 duced. It is evidently owing to the different periods of time that the in- 

 sects remain in the pui^a state. 



