PALMER WORM EARLY NOTICES OF IT. 221 



A pale yelloAvish green worm having a dusky or blackish stripe along 

 each side of the back with a narrower whitish stripe on its upper side 

 and a dusky line in the middle, and a shining yellow head, the hue 

 of beeswax; residing in worm-eaten leaves drawn together by silken 

 threads, and when jarred, dropping and hanging in the air suspended 

 by threads; appearing the latter part of June, at times excessively 

 numerous. 



The Palmer-worm, Chatochilus pometellus, Harris, (Plate 4, fig. 4.) 



Though not abundant, this worm is common upon the leaves 

 of orchards and forests, making its appearance every year about 

 the middle of June and continuing till the last of the month. 

 But it sometimes becomes multiplied in a most astonishing man- 

 ner, appearing suddenly in prodigious numbers over a vast ex- 

 tent of country, in a single day changing the green foliage every- 

 where to a withered brown hue, as though it had been scorched 

 by fire. And after continuing a week or two it disappears as 

 suddenly as it came, so that on a tree which to-day contains 

 hundreds of these worms, to-morrow not one can be found. 

 And the following year when the same season comes round and 

 we are looking for multitudes of these insects to make their 

 appearance again, no traces of them are to be seen. 



As this worm comes forth nearly a month later in the year 

 than the apple tree caterpillar spoken of in the foregoing pages, 

 it is much more destructive to the trees. When their foliage is 

 stripped off and destroyed by this worm, only a slight crop of 

 leaves puts out upon them after it disappears. Old trees 

 and many of the limbs upon young thrifty trees die; and 

 after a visitation of these worms, should the weather during 

 the month of July'prove to be dry, and hot, as it frequently is, 

 the damage is much more extensive, whole orchards and forests 

 perishing. 



At a former period when the surface of our country was 

 covered with one continuous forest it must have been a singular 

 and sad spectacle to see the timber over such vast districts all 

 blighted and leafless, as it doubtless was at times, from havrng 

 been overrun by these worms. It is most probably these insects 

 to which the Sweedish naturalist, Kalm, in his travels through 

 this country a century ago, alludes in the following passage, 

 (vol. ii, p. 7.) " There is likewise a kind of caterpillars in these 



