5M 



FAMILY SCOLYTIDAE 



changes into a pupa within this. Fig. 333 and pi. xlix show pieces of bark 

 completely covered with the pairing-chambers, egg-galleries, larval galleries, 

 and pupating-chambers. The pupa turns gradually into the immature 

 beetle, and the latter remains for a time resting in the chamber whilst 

 its outer parts are slowly hardening and it is becoming darker in colour. 



FlG - 333- Egg and larval galleries of J'olygrap/nts trenchi, Steb., on inner bark of 



rinns gcranliana. North Zhob, 1905. 



/hen fully mature, the beetle bores straight out of the bark by a 



eaten out horizontally from the spot where it is lying. In the 



spring generation, when the weather is still comparatively 



as much as five weeks are probably spent in the larval stage and a 



