78 MOTHS 



PLATE XL 

 THE PEBBLE HOOK-TIP (3) 



Five different kinds of "hook-tip" moths are 

 found in the British Islands, and you can tell 

 them at once by the hook-like tip to their front 

 wings. The Pebble Hook-tip is by far the 

 commonest of the five. If you want to find it, 

 the best way to do so is to shake the branches 

 of birch trees, either in May, or in August, for 

 this is one of the "double-brooded" moths. That 

 is, they make their appearance twice in each 

 year, the eggs laid by the spring brood produc- 

 ing moths in the summer, while those laid by 

 the summer brood produce moths in the following 

 spring. 



The caterpillar of this moth is rather curiously 

 shaped, for its tail — which it always holds up in 

 the air — is drawn out into quite a sharp point. 

 It has a grey head and a light green body, with 

 a purple stripe down the back. It feeds on the 

 leaves of birch trees, and when it has reached 

 its full size it doubles over a corner of one of 

 the leaves, fastens it firmly down by means of 

 a number of silken threads, and then turns into 

 a chrysalis. 



