BRITISH BUTTERFLIES AND MOTHS i 



are found one may expect to locate it. Sallow and 

 willow are also frequented, and the eggs (usually two in 

 number) are laid on the upper (not the under) surface of 

 the leaves. When first hatched, the small fluffy black larva 

 hardly seems capable of evolving into the large for- 

 midable creature of later days, but as it feeds ravenously 

 it increases in stature, and becomes more interesting at 

 each successive stage of development. When it is full- 

 grown, the larva has a large black and red face, a 

 hump at the back of the head, and a body that tapers 

 perceptibly towards the curious whisp-like " tail." The 

 green colour is relieved with a dark band on the back, 

 with light edging. I have watched the larva prepare for 

 pupation under very favourable circumstances, and on 

 one occasion it performed the operation in a small 

 wooden box which I carried in my pocket. When I 

 showed the full-grown larva to an eager class of boys 

 at three o'clock one July day, it crawled about my hand 

 (and theirs !), but an hour later, when I prepared to 

 exhibit it to a class of girls, it had actually entombed 

 itself in a cocoon composed of tiny portions of the 

 wooden lid, had coiled itself up, and was ready to go to 

 sleep. It had scooped out a hollow in the lid of the box 

 with its strong jaws, and the particles of material secured 

 had been glued together into a thimble-shaped cocoon 

 which was already quite hard. A reddish-brown pupa 

 was eventually contained within the cocoon, but I had 

 to wait until the following May before the perfect 

 insect emerged from the shroud, the old pupa case 

 remaining inside. In a natural state the cocoon is 

 found on the trunks of trees, palings, and similar places, 



