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COCOONS, BUT NOT OF SILK. 
rough when it is finished. But one small cater¬ 
pillar contrives to make an elegant cocoon, not 
of the hark, but of the outer skin of the twig. 
It peels it off very fine indeed, and cuts it into 
narrow strips, so narrow that they look like 
feathers. These it laces together with such ex¬ 
quisite nicety, that you cannot see the joins. 
It is wonderful how this little creature, without 
any tools but its feet and its mouth, contrives to 
work so well. But Nature has given it the patience 
and skill to execute the delicate task; and when 
it is finished, the caterpillar lines it with silk, 
and changes into a chrysalis within it. When 
the moth comes out, she is so like the colour of 
the twig, that you can hardly distinguish her. 
But very often the caterpillar will burrow into 
the earth, and form its cocoon below the surface. 
There are some sand hills, on the coast of 
Devonshire, into which numbers of caterpillars* 
dig for security. They feed upon the sea spurge, 
and will hardly touch any other kind of plant. 
When the autumn comes, they descend in a body, 
and hide themselves in the sand, forming loose 
cases of earth for cocoons. Here they lie till the 
following summer, and sometimes even till the 
summer after that; when they come out moths, 
with green and rose-coloured wings. 
* Of Sphinx Euphorbia. 
