Reports to various Correspondents. 



85 



coming from the egg in about eight days at once bores into 

 the shoot and causes the resin to exude, which forms the nest in 

 which it lives. This nest is at first very small, but becomes as large 

 as a pea or even a hazel nut by the winter, and is quite hollow ; in 

 this the caterpillar passes the winter. In the spring it commences 

 to feed again, and the nest continues to gi'ow. This nest eventually 

 may reacli the size of a walnut, the resinous walls being irregular 

 outside. The nest may be on the underside of the shoot, or may, as 

 in most of the specimens sent from 

 Dores completely surround the shoot. 

 At first it consists of only one 

 chamber, but tlie mature nest is 

 found to be divided into two com- 

 partments or rooms, as Mr. Fraser 

 describes them. One, the larger, is 

 used as the dwelling-place of the 

 caterpillar, the smaller one is used 

 for the excremetit or " frass." The 

 larva is rather more than two-thirds 

 of an inch long, orange-brown in 

 colour, with brown head and thoracic 

 shield. They attain their full size 

 in October, and then pass the winter 

 in a thick white web in the nest. 

 The larva pupates in April and 

 May of the third year. The pupae 

 are black when mature, but at first 

 are dull white, gradually changing 



to brown ; but some of the mature ones had brown aljdomens. When 

 the larvas are in danger, according to Kollar, they let themselves down 

 to the ground by a thread and ascend again at leisure. 



The resin that forms the nest exudes from the hole formed by the 

 young larva, and this continues to flow iox a long time, probably 

 through the continued action of the grub. The shoot above the nest 

 often dies right away, numerous side shoots being thrown out below 

 the nest. 



The only method of treatment is to cut oft' and burn the nests 

 during the second year. 



Fig. 15. — nkst of Retinia resinella. 



