Feb., 1906.] Notes on the Fall Webworm in Ohio. 
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upon a hedge of osage orange, at Berea, Ohio. Closer investiga- 
tion, however, revealed the fact that the web was not upon the 
osage orange at all, but upon a small wild cherry tree that grew 
in the hedge and which had escaped my notice. 
Walnut Trees . — Only a few walnut trees exist at the Point, 
but the worms played havoc with these, while of all the great 
abundance of choke-cherry, only two instances were noted 
where the infection was at all so extensive. A clump of five 
walnut trees (each about six inches in diameter), became liter- 
ally defoliated and about 150 nests were counted upon them. I 
have observed, however, that the number of webs does not 
necessarily indicate the number of broods, since a large brood 
mav desert its old nest, and build a new one, or divide and form 
two new nests. (I use “nest” to distinguish the denser part of 
the web. See also Other Observations.) 
When food became scarce the worms began to migrate down 
the trunks of the trees, here and there covering the limbs and 
trunks with web. This migration occurred chiefly at night, the 
worms generally resting, as usual during the day, in temporary 
webs frequentlv located at the base of the trees and of extraor- 
dinary size. In one instance I estimated that not less than two 
quarts of worms occupied a certain web. 
In the earlv part of the forenoon I usually found some strag- 
glers which had been overtaken by daylight, evidently en route 
from the trees. Many of these were found dead in small pits, 
from which, as experiment showed, they had been unable to 
extricate themselves, and had died from the excessive heat. 
The worms migrated mainly eastward to a clump of choke- 
cherry nearby and westward to a large hackberry about forty 
feet distant. This migration continued during about ten days. 
In four days the mxmber of nests in the choke-cherry bush 
increased from six to twenty-five and the bush was literallv 
stripped as the worms advanced. 
The migration to the hackberry was not so striking as that 
to the choke-cherry bush but even more interesting. At first 
the worms congregated in the crotches of the larger limbs but 
advanced upward from day to day and formed webs in the 
smaller branches. They soon began to strip the leaves and the 
webs could then be seen at some distance from the outside of the 
tree. 
Mr. W. B. Herms, who remained at the Laboratory until 
August 31st, was kind enough to observe the worms for me and 
reported that after my departure the worms migrated only a 
little farther east into the choke-cherry bushes and became 
fewer in number. I presume that they were then mature and 
that they wandered away to pupate. The trees began to show 
new life and by the time IMr. Herms left were quite green again. 
