A LOCOMOTIVE PUPA. 219 



contained in two large sacs within the body, and 

 softens the silk so that it can be easily broken. It 

 then throws off the caterpillar skin and becomes a 

 chrysalis, which is at first white and soft, but after- 

 wards hard and brown. The edges of the segments 

 are furnished with little points directed backwards, 

 and by alternately stretching and contracting the 

 abdomen, the pupa forces itself along its larval tunnel 

 until it comes to the end. Just before the final trans- 

 formation the pupa renews its efforts, and fairly 

 pushes itself through the thin shell of bark that has 

 been allowed to remain by the larva. 



It still continues to push its way on until it has 

 forced itself through the opening, as far as the base of 

 the abdomen. After a while the pupal skin splits, 

 and the Moth emerges slowly, climbing up the bark 

 of the tree, and there clinging while it shakes out its 

 wings. The empty pupa skin remains at the entrance 

 of the tunnel, and towards the middle or end of 

 summer, according to the season, plenty of these 

 empty shells may be found projecting from trees that 

 are infested with the Goat Moth larva. The Moth 

 itself can generally be captured upon the bark of the 

 tree in which it has passed its pupal state. 



The willow is the tree that is usually infested by 

 this insect, and vast damage is often done by it. 

 Other trees, however, are attacked by this destructive 

 insect, especially the elm, and Mr. Newman is of 

 opinion that those trees which are apparently killed 

 by the Scolytus have received their death-blow from 

 the Goat Moth, and have only been attacked by the 

 Scolytus when dying. 



