784 
[Assembly 
where it lies, and to these the skins of any dead plant-lice or 
particles of dirt which may be within reach are affixed, to serve 
as more convenient points of attachment for the threads which 
are aftenvards spun than what the naked threads would be. In¬ 
side of these the insect lies, with its tail plajing around back¬ 
wards and forth. At first the skin is so distended and the body 
so stiff that it can only bend inwards in the form of a semicircle 
or of a horse-shoe, and the head is thus brought opposite the tail, 
giving the insect a ludicrous aspect as it lies still, with its eyes 
gazing fixedly at the tail as if in astonishment at seeing it fly 
around in such a singular manner. The tail at this times reaches 
around to every part of the half of a sphere, and w r hen one side 
has become sufficiently filled with threads, the body moves along 
to give it access to another side, the insect thus lying at one time 
upon its side or its back, and at another time standing as it w'ere 
upon its head. Occasionally, as if tired with its cramped position 
it straightens out somewhat, thus putting the threads upon the 
stretch and moulding the sides of the cavity in width it lies into 
a smooth and even surface. As so much matter is given out from 
its body to form the threads of the cocoon, the skin ceases to be 
distended as it was at first, the body shrinks and becomes more 
flexile, and as the cavity in which it lies becomes more and more 
contracted in size by the threads which the tail is constantly add¬ 
ing on every side, the insect is draw r n together into a smaller 
space and becomes coiled into the form of a ball, the. head being 
pressed down upon the breast, with the tail directly over it briskly 
continuing its work in the small vacant space which here remains. 
The feet are now so cramped that they are incapable of turning 
the body around as at first, and it now only moves along slightly 
by a vermicular motion often repeated. The threads have now 
become so numerous and close that finally no open meshes are 
left between them, and thus a small ball of‘paper-like texture is 
formed in the centre of the cocoon, within which the insect is 
entirely hid from view, tightly bandaged like the feet of a Chinese 
lady and compressed to a quarter of its previous size. This is 
a most remarkable circumstance in the history of these insects— 
that the lame contract and compress themselves into cocoons of 
scarcely one-fourth their size, and from these cocoons come flies 
