416 
LEPIDOPTERA. 
and about half an inch in diameter. It was not regularly 
oval, but somewhat flattened on its lower side. It consisted 
externally of two oblong oval pieces of a leaf, fastened to¬ 
gether in the neatest manner by their edges, but the seams 
made a little ridge on each side of the case ; this had become 
dry and faded, and was lined within with a thick and tough 
layer of brownish silk, in which there was left, at each end, 
a circular opening just big enough for the caterpillar to pass 
through. The caterpillar (Fig. 206) was 
cylindrical, about as thick as a common 
pipe-stem, of a light reddish-brown color 
with a paler line along the back; it was 
rough with little elevated points; its head 
and the top of the first ring were black, 
hard, and rough also. The head was provided with a pair 
of jointed feelers, which the insect extended and drew in at 
pleasure, and which, when they were out, were kept in con¬ 
tinual motion. On each side of the middle of the head, 
there was a black and flexible kind of antenna, very slender 
where it joined the head, and broader towards the end, like 
the handle of a spoon. The first three pairs of legs were 
equal in length, and armed with stout horny claws. The 
other legs, if such they could be called, were ten in number, 
and so short that only the oval soles of the feet were visi¬ 
ble, and these were surrounded by numerous minute hooks. 
The tail end of the body was as blunt as if it had been cut 
off with a knife; it sloped a little backwards, and consisted 
of a circular horny plate, of a dark gray color, which, when 
the caterpillar retired within its case, exactly shut up one of 
the holes in it. This caterpillar eat the leaves of the oak, 
and fed mostly by night; while eating, it came dialf-way, or 
more, out of its cocoon; and in moving laid hold of the leaf 
with its fore legs, and then shortened its body suddenly, so 
as to bring its cocoon after it with a jerk ; and, in this way, 
it went by jerks from place to place. When it had dono 
eating, it moored its case to a leaf by a few silken threads 
Fig. 206. 
