Plate IX. 
k 
i 
i 
Figs. 1 and 5 . Peridermimn cerebrum on Lodge Pole pine {Pinus murrayana.) 
Fig. 2. P. alnetinum. 
Figs. 3 and 4. P el atinum on Abies subalp iv a. 
Fig. 6. Peridermium on Pieea engelmannii. 
sp-spores; m- mycelium; c-cavity of tracheid; p-peridial cells. 
L. H. Pammel and Charlotte M. King. 
