34 THE AMERICAN SILK WORM. 
the inside of the cocoon. The process of exclusion from 
the cocoon lasts for as much as half an hour. The insect 
seems to be instinctively aware that some time is required 
to dissolve the gum, as it does not make any attempt to 
open the fibres, and seems to wait with patience this 
event. When the liquid has fully penetrated the cocoon, 
the pupa contracts its body, and pressing the hinder 
end, which is furnished with little hooks, against the 
inside of the cocoon, forcibly extends its body; at the 
same time the head pushes hard upon the fibres and a lit- 
tle swelling is observed on the outside. These contrac- 
tions and extensions of the body are repeated many times, 
and more fluid is added to soften the gum, until under 
these efforts the cocoon swells, and finally the fibres sepa- 
rate, and out comes the head of the moth. In an instant 
the legs are thrust out, and then the whole body appears ; 
not a fibre has been broken, they have only been sepa- 
rated. | 
To observe these phenomena, I had cut open with a 
razor, a small portion of a cocoon:in which was a living 
chrysalis nearly ready to transform. The opening made ~ 
was covered with a piece of mica, of the same shape as 
the aperture, and fixed to the cocoon with mastic so as to 
make it solid and air-tight ; through the transparent mica, 
I could see the movements of the chrysalis perfectly well. 
When the insect is out of the cocoon, it immediately — 
séeks for a suitable place to attach its claws,’so that the 
wings may hang down, and by their own weight aid the : 
action of the fluids in developing and unfolding the very 
short and small pad-like wings. Every part of the insect. 
on leaving the cocoon, is perfect and with the form and 
size of maturity, except the pad-like wings and swollen 
and elongated abdomen, which still gives the insect @ 
Seg rere eee te 
