106 MOTHS AND BUTTERFLIES. 
the upper part of the body just back of the head and a large yellow 
one near the tail end. Numerous small blue warts occur in regular 
order on the back and sides. The head, legs and posterior part of 
the body are yellow. While feeding these caterpillars usually re- 
main among the tender leaves on the new growth, and several are 
generally found in close proximity. On reaching maturity the 
caterpillar descends to the lower part of the bush and begins spin- 
ning its cocoon. After selecting a leaf suitable for its purpose, it 
commences by spinning a quantity of silk along the branch and 
down the stem of the leaf in order to make it secure for the winter. 
Cocoon of Attacus promethia. 
It then draws the sides of the leaf together with silk, and therein 
spins its tough, brownish cocoon. The silk is very strong, and the 
cocoons are attached so firmly to the twigs by their slender cord that 
they ride secure for the winter. In fact, one may often find cocoons 
which have weathered the blasts of several seasons still firmly at- 
tached. The upper end of the cocoon, which is double like Attacus 
cecropia, is so loosely spun that the moth has little difficulty in fore- 
ing its way out. This silk could probably be made useful in the 
arts, as it is very strong and durable and the caterpillars could be 
reared in the open air in countless thousands with little difficulty. 
The moths emerge from the cocoons the latter part of June and 
the first of July, the females differing so much from the males as 
easily to be mistaken for different species. The male is a very oily 
