336 PROTECTION AGAINST INSECTS. 



silvery marks, hind-wings dark grey ; both pairs with light 

 grey fringes. Thorax orange, abdomen grey. 



Caterpilhir 14 mm. long, with 10 prolegs, bright brown and 

 smooth, the head and first segment black. 



Pupa yellowish-brown, with a row of fine prickles on the back 

 of the abdomen. 



/'. Life-h is/or//. 



The moth appears from the end of Jane till the end of July. 



During the day it sits somewhat concealed amongst the pine 

 needles, its colour assimilating with the withered pine shoots, 

 but it becomes active with the approach of twilight. The eggs 

 are laid among the terminal buds of young Scots pine plants. 

 The caterpillars hatch out at the end of August and in 



^^1^^ 



Fig. ITl.— Torlrix huoUana, Schiff. 

 a Imago, h Larva, e Pupa. 



September, tliey hibernate in the Inids, becoming full grown in 

 the following May. 



Pupation takes place at the end of May or June, at the base 

 of the injured shoot. Tiie pupa is exposed, and the empty 

 pupal case may be seen for some time on the shoot. 



The moth emerges 4 weeks later. 



Generation annual. The insect is common and widely 

 distributed wherever Scots pine trees are grown in Europe. 



c. Relations to the Forest. 



The Scots pine and occasionally the Weymouth, l)lack and 

 cluster pines are attacked. * 



The insect exclusively attacks young growth, and prefers 

 weakly G- to 12- year-old plants on poor soil and in sunny 

 situations. 



