246 LIFE AND HER CHILDREN. 
Out of just such cocoons as this, but of coarser 
make, with a tiny hole left at one end, come the 
beautiful emperor-moth, the night peacock, and the 
curious Oak-eggar moth, whose caterpillar sleeps 
all through the autumn and winter before beginning 
to feed and spin its cocoon ; while the Burnet moths 
Fig. 83. 
The six-spot Burnet-Moth.* 
c, Caterpillar ; co, cocoon ; m, perfect moth. 
(Fig. 83) often spin very thin cocoons covered with 
a kind of varnish which makes them as strong as 
parchment. With a little trouble you may often find 
the empty cases of these and other moths left on the 
grass and bushes in July and August, when the insects 
are fluttering over the gardens and fields. But the 
* Zyg&na filipendulcB, 
