26 E Canadian Arctic Expedition, 1913-18 
EXPLANATION OF PLATE IIL 
Plate 2. Spruce from Coppermine River forest, below Sandstone rapids. 
Fig. \. Section showing work of Polygraphus ntfipennis Ky., beneath the bark. 
Fig. 2. Spruce branch showing tunnels of Carphoboriis andersoni S\v. 
Fig. 3. Spruce branch showing tunnels of Xylotrcchits uNchdatus and Neodytus muriaitidut 
Fig. 4. Same as figure 3, the reverse side. 
