1912] 



The Ottawa Naturalist. 



143 



Tunnels>of$PoLYGRAPHUS rufipennis Kirby, in spruce bark. Three stages in : the 

 development of the egg-tunnels. * 



et - 



-* Dendroctonus simplex Lee. Development of larval galleries; larva: half-grown: e.t., 

 egg-tunnels; 1. g., larval galleries. 



Dendroctonus simplex Lee. An egg-tunnel showing egg-pockets; e. p., containing 

 eggs; turning-niches, t. n., and entrance-hole. e. h. 



