THE ATTACUS CECROPIA. 389 



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 following 

 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 does 

 not contain much floss silk. So strong is the coating 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. 



