LEPIDOPTERA. 159 
causing the greater part of them to curve at their upper extremity, 
in such a manner as to form a sort of cradle. 
It remains for us now to speak of the caterpillars that make 
their cocoons of silk, together with other materials. Réaumur saw 





Fig. 118.—Small Caterpillar of the Pimpernel. Fig. 119.—Cocoon of the same. 
the Pimpernel caterpillar arranging and sticking together the 
leaves of that plant, and spinning underneath them a thin cocoon 
of white silk (Fig. 119).. 
Some caterpillars make their cocoons on the surface of the 
earth, and even with earth. These cocoons are spherical or 
oblong. Their exterior is more or less well shaped, but their 
interior is always smooth, polished, shining like moistened earth, 
worked up together into a kind of paste, and carefully smoothed 
out. This cocoon is besides lined with a covering of silk of 
variable thickness. The shell is not made of earth alone; threads 
of silk may be seen in it, crossing each other, and binding 
together the particles of earth. 
These subterranean workers do not allow their proceedings to 
be easily observed. Réaumur was fortunate enough to be able to 
discover the artifice they employ in the construction of their shells 
or cocoons. The Cucullia verbasci (Fig. 120) makes itself a 
thick and very compact cocoon of the form of an egg (Fig. 121). 
Réaumur took one of these out of the ground before it was 
fortified. He tore it partially open, and placed it in a glass 
vase containing sand, but the poor insect was not long in repair- 
ing the disorder caused by the rough hand of our naturalist. It 
only took four hours to restore its cocoon to its former state. 
“Tt began,” says Réaumur, “by coming almost entirely out, 
