160 THE INSECT WORLD. 



and left only its hinder part within. It moved its head forwards 

 as far as was necessary to enable it to seize a particle of earth. 



Fig. 120. Cucullia verbasci. 



As soon as it had got its load, it re-entered the interior of the 

 cocoon. It deposited the grain of earth, and came out again im- 

 mediately, as it did at first, to pick up another grain, which it 

 carried likewise into the interior of the cocoon. This operation 



it continued for more than an hour. 

 .... The provision of materials 

 being got together, the caterpillar 

 now devoted its whole attention to 

 working them up. It began by 

 spinning over one part of the edges 

 of the opening. After having put 



Fig. 121. Cocoon of the Cucullia verbasci. * 



over this a small band 01 very loose 



web, the caterpillar's head left the opening, the insect went right 

 back again into its cocoon, and the head returned to the opening 

 loaded with a little grain of earth, which it entangled in the silky 

 threads. It then entangled in them two or three, or a greater 

 number of grains, according to the quantity of threads it had 

 spun. It bound them into these with other threads,, after 

 which it drew threads over the edges of another part. By 

 thus going round the whole rim of the opening, and by carrying 

 and fixing the grains of earth in the threads which were the last 

 stretched over the opening, it rendered its diameter smaller and 

 smaller/' 



It was by working with its head that our mason gave to the 

 new wall of its cocoon the necessary curvature. It was interest- 

 ing to know how, as it could no longer put out its head, it could 

 stop up the orifice. 



