COLKOPHORA LAUICKLLA. 



347 



The little caterpillar, as soon as it has emerged from the 

 egg, bores into the young larch-needles to about half their 

 length, so that their upper ends shrivel up and turn yellow, as 

 if injured by frost. The attack usually commences on the 

 lower branches and proceeds upwards, the top of the tree 

 being spared in moderate attacks. 

 The appearance of a plant which 

 bears a large number of infested 

 needles is very conspicuous and 

 characteristic. 



In September the fully grown 

 caterpillar prepares a little case out 

 of the dry part of the needle, which 

 it cuts off for the purpose, and in 

 this it hibernates on the twigs, 

 usually at their tips, or in bark- 

 cracks, or among lichens on the 

 stems. 



In the spring the caterpillar, carry- 

 ing its case with it, bores again about 

 half-way into a larch needle, and 

 about the middle of April finding its 

 old case too small, it fastens it along 

 the freshl}^ hoUowed-out needle, like 

 two fingers of a glove. It then cuts 

 out the adjacent walls of its old case 

 and of the needle, thus preparing a 

 new case twice as wide as the 

 former. This troublesome work occu- 

 pies several days, during which an 

 observer might imagine that there 

 were two larvae on a needle. When 

 the insect is ready for pupation it spins the new case firmly 

 to a needle. . 



The little insect likes sunny warm localities, sheltered from 

 the north and east, and prefers the westerly borders of woods, 

 avoiding isolated trees, probably on account of their exposed 

 position. It has been observed in Switzerland up to an 

 altitude of 3,000 feet, and in Germany and Britain it constantly 



Fig. 179. —Larch -needles in- 

 jured by C. laiicclla, Hbn. 

 [Xatiiral size.) 



a Larval cases. h Spinning 

 catei-pillars. c Hollowed 

 and twisted needles. 



