378 
ANNUAL REPORT OF NEW-YORK 
CIIKRRY. LEAVES. 
my yard without one of these worms ever appearing upon it; 
whilst upon an ash tree standing beside this sassafras and not 
three feet distant from it there lias repeatedly been a family of 
these worms. Certainly if the sassafras were the favorite food of 
this species some of these worms would have been placed upon it. 
They have also occurred upon ash trees in other parts of my 
grounds, and upon no other tree have I ever met with them. Last 
year on the 18th of July a dozen young worms were found in a 
cluster upon the under side of a leaf of the ash tree above alluded 
to, and upon an adjacent leaf of the same stalk were the shells 
of the eggs from which these worms had come, resembling little 
cups or hemispheres of clear glass. The eggs were in contact 
with each other on the under surface of the leaf, and this leaf 
had been partly consumed by the worms when they first came 
from their shells. I continued to notice them daily for about a 
week, when they all disappeared, probably mounting high into 
the tree, and I could discover no traces of them afterwards. Upon 
the fall of the leaves in autumn I was disappointed to find no 
cocoons upon this tree; but upon a lilac growing against the side 
of the house four rods distant two dozen cocoons occurred. The 
worms which formed these cocoons could not have fed upon the 
lilac without being discovered, and I could not avoid the conclu¬ 
sion that they had been reared upon the ash tree, and when fully 
grown had migrated to this bush, though in doing so they passed 
several other lilac bushes, and selected this, perhaps, because 
growing against the side of the house it would be less apt to be 
visited by birds than those standing in the open yard. Eut this 
precaution did not save them. The last winter being unusually 
long and severe, our winter birds were obliged to forage more 
assiduously than usual, and before spring every one of these 
cocoons were perforated and its inmate destroyed. In other 
instances I have noticed these w r orms remaining till they u r ere 
mature, upon small sprouts of the ash where they could be 
observed daily. From all these facts I am confident the ash is 
their favorite food. But when ready to spin their cocoons it is too 
laborious a task for them with their silken threads to tie the long 
leaf stalks of this tree to the limbs from which they grow, and I 
have very seldom known a cocoon to be placed upon this tree. 
