ILLUSTRATIONS. 



PLATES. 



Page 

 Plate I. Fig. 1. — Sporophores of Polyporm schweinitzii Fr. Fig. 2. — Polyporus 

 volvatus Peck, growing from holes made in the bark by Dendrodo- 



rms sp ^6 



II. Log of Balsam Fir showing decay caused by Polyporus schweinitzu Fr. 56 



III. Log of White Spruce showing early stage of decay caused by Poly- 



porus pinieola (S wartz ) Fr 56 



IV. Log of White Spruce showing advanced stage of decay caused l)y 



Polyporus pinieola (Swartz) Fr 56 



V. Sporophores of Polyporus pinieola (Swartz) Fr 56 



VI. Fig. 1.— Red Spruce: Early stage of the decay caused by Tramefes 

 pini forma abietis. Fig. 2.— Red Spruce: Advanced stage of the 



decay caused by Tramcies pini forma abietis 56 



VII. Log of Balsam Fir showing decay caused by Trametes pini forma 



abietis 56 



VIII. Fig. 1 early and fig. 2 late stage of decay of Larch caused by Trametes 



pini forma abietis 56 



IX. Polyporus subaddus Yk., Polyporus pinieola (Swartz) Fr.,and Trametes 



pini (Brot.) Fr. forma abietis Karst 56 



X. Work of Polyporus pinieola (Swartz) Fr. and Trametes p)im (Brot.) Fr. 



forma abietis Karst 56 



XL Stages of decay induced in Spruce by Pohjporus subaddus Pk. and 



Polyporus sulfureus ( Bull. ) Fr 56 



XII. Various forms of sporophores of Trametes pini (Brot.) Fr. forma 



abietis Karst 56 



XIII. Block of White Spruce wood showing injury caused by Polyporus 



sulfurexis 56 



XIV. Fig. 1 early stage and figs. 2 and 3 successively later stages of the 



decay caused in White Spruce by Polyporus subaddus Peck 56 



XV. Fig. 1.— Cross section of log of Spruce showing decay caused by Poly- 

 porus subaddus Peck. Fig. 2. — Resupinate form of sporophore of 

 Polyporus subaddus Peck on Spruce log 56 



TE.XT FIGURES. 



Fig. 1. Polyporus schvjeinitzii Fr. growing on a fallen Fir 21 



2. Cross section of Spruce wood showing masses of mycelium of Polyporus 



jnnicola (Swartz ) Fr 28 



3. Base of Spruce branch, showing its resistance to the attack of the 



mycelium of Polyporus subaddus Pk •*' 



7 



