LEPIDOPTERA . 155 



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. Reaumur saw 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, 



Fig. 120. Larva of Cucullia verbasci. 



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 vari- 

 able 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 Fig . I2I ._ C ocoon of the Cu 

 easily observed. Reaumur was for- 

 tunate enough to be able to notice their skill 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). 

 Reaumur took one of these out of the ground before it is fortified. 

 He tore it partially open, and placed it in a glass vase containing 

 sand, but the poor insect was not long in repairing the disorder 

 caused by the rough hand of our naturalist. It only took four hours 

 to restore its cocoon to its former state. 



" It began," says Reaumur, " by coming almost entirely out, and 



