278 STATES OF INSECTS. (Pupa.) 
furnished by the flask-shaped brown one of Saturnia 
Spini, and some other moths. If you examine one of 
these cocoons, which are common enough in some places 
on the pear-tree or the willow, you will perceive that it 
is generally of a solid tissue of layers of silk almost of 
the texture of parchment; but at the narrow end, or 
that which may be compared to the neck of the flask, 
_that it is composed of a series of loosely-attached longi- 
tudinal threads, converging, like so many bristles, to a 
blunt point, in the middle of which is a circular opening?. 
It is through this opening that the moth escapes. The 
silk of its cocoon is of so strong a texture and so closely 
gummed, that had both ends been similarly closed, its 
egress would have been impracticable; it finds, however, 
no difficulty in forcing its way through the aperture of a 
sort of reversed funnel, formed of converging threads 
that readily yield to pressure from within. But an ob- 
jection will here probably strike you. You will ask, Is 
not this facility of egress purchased at too dear a rate? 
Must not a chrysalis in an open cocoon be exposed to 
the attacks of those ichneumons of which you have said 
so much, and of numerous other enemies, which will find 
admittance through this vaunted door? Our caterpillar 
would seem to have foreseen your dilemma; at least, un- 
der heavenly guidance, she has guarded against the dan- 
ger as effectually as if she had. If you cut open the co- 
coon longitudinally, you will see that within the exterior 
funnel-shaped end, at some distance she has framed a 
second funnel, composed of a similar circular series of 
stiff threads, which, proceeding from the sides of the co- 
* Sepp. iv. ¢. xi. ft ms 
