THE AMERICAN SILK WORM. 33 
were the originators of the large number which I have 
cultivated since. Of these three hundred worms, I lost a 
great many, not knowing their wants, but I succeeded in 
obtaining twenty cocoons in the autumn. It was only in 
1865 that I became expert in cultivating them, and in 
that year not Jess than a million could be seen feeding in 
the open air upon bushes covered with a net; five acres 
of woodland were swarming with caterpillar life. 
Natural History of Telea Polyphemus. Early in sum- 
mer, the chrysalis of Polyphemus which has been for eight 
or nine months imprisoned in its cocoon, begins to awaken 
from its long torpor, and signs of life are manifested by 
the rapid motion of its abdomen. In the latitude of Bos- 
ton, the earliest date at which I have seen a perfect insect 
is the twentieth of May. From this time until the middle 
of July, the moths continue to come out of the cocoons. 
The cocoon being perfectly closed, and a hard gummy, 
resinous substance uniting its silken fibres firmly toge- 
ther, it is quite hard for the insect to open it, as it has no 
teeth, nor instrument of any kind to cut through it, and 
the hooked feet are far too feeble to tear such a dense 
structure. : 
But the moth must have some means of exit from the co- 
coon. In fact they are provided with two glands opening 
into the mouth, which secrete during the last few days of 
the pupa state, a fluid which is a dissolvent for the gum 
so firmly uniting the fibres of the cocoon. This liquid is 
composed in great part of bombycic acid. When the in- 
sect has accomplished the work of transformation which is 
going on under the pupa skin, it manifests a great activ- 
ity, and soon the chrysalis-covering bursts open longitu- 
dinally upon the thorax; the head and legs are soon dis- 
engaged, and the acid fluid flows from its mouth, wetting 
AMERICAN NAT. VOL. I. 5 
