THE WISE CADDIS-WORM 77 



up it casts its skin, and there in its place is a 

 strange-looking white pupa, with two black 

 eyes, a parrot's beak, a pair of antennae, and 

 six slender legs which for the present lie limply 

 pressed against its sides. 



This strange pupa lies quietly in its old case 

 at the bottom of the pool while its wondrous 

 transformation is taking place. Soon instead 

 of a Caddis-worm it will be a Caddis-fly a 

 pretty, greyish fly that looks very much like a 

 moth. Its wings are large, and when closed, 

 meet over the insect's back like a little slanting 

 roof. 



But before it can become a fly the Caddis 

 must leave the water, and we left it lying as a 

 pupa at the bottom of the pond, shut up in 

 its old case. How is it going to get out ? 



Well, as soon as it is quite ready to make 

 its last change the pupa breaks open the end 

 of its case with its funny parrot's beak, and 

 pushes its way out into the water. Directly 

 it is free we see the use of its six thin legs, 

 for this pupa is able to swim and run about 

 quite nimbly. But it must not stay long in 

 the water ; that would not be at all a safe 

 place for such a soft, defenceless creature ; so 

 the pupa swims a little way on its back, and 



