II. 25, D:v. Veg. Pri^s. 6c Path., U S. Dept. of Agncu'tur 



Plate I. 



Fig. 1.— Sporophores of Polyporus schweinitzii Fr. 



Fig 2.— Polyporus volvatus Peck, growing from holes made in the bark 

 BY Dendroctonus sp. 



