THE ATTACUS CECROPIA. 
389 
Fig. 185 
in diameter at the widest part. Its shape is an oblong oval, 
pointed at the upper end. It is double, the outer coat being 
wrinkled, and resembling strong 
brown paper in color and thick¬ 
ness ; when this tough outer coat 
is cut open, the inside will be 
seen to be lined with a quantity 
of loose, yellow-brown, strong 
silk, surrounding an inner oval cocoon, composed of the 
same kind of silk, and closely woven like that of the silk¬ 
worm. The insect remains in the chrysalis form through 
the winter. The moth, which comes forth in the followinor 
summer, would not be able to pierce the inner cocoon, were 
it not for the fluid provided for the purpose of softening the 
threads; but it easily forces its way through the outer cocoon 
at the small end, which is more loosely woven than else¬ 
where, and the threads of which converge again, by their 
own elasticity, so as almost entirely to close the opening 
after the insect has escaped. 
A few brown and curled leaves may frequently be seen 
hanging upon sassafras-trees during the winter, when all 
the other leaves have fallen off. If one of these leaves is 
examined, it will be found to be retained by a quantity of 
silken thread, which is wound or woolded round the twig 
to the distance of half an inch or more on each side of the 
leaf-stalk, and is thence carried downwards around the stalk 
to an oval cocoon, that is wrapped up by the sides of the 
leaf. The cocoon itself is about an inch long, of a regular 
oval shape, and is double, like that of the Cecropia cater¬ 
pillar ; but the outer coat is not loose and wrinkled, and the 
space between the outer and inner coats is small, and docs 
not contain much floss silk. So strono; is the coatino; of silk 
that surrounds the leaf-stalk, and connects the cocoon with 
the branch, that it cannot be severed without great force ; 
and consequently the chrysalis swings securely within its 
leaf-covered hammock through all the storms of winter. 
