SPORES HYALINE. 



firm below. Pores medium large, about 2 mm. deep, with angular, 

 irregular mouths, white, discolored in drying. Spores globose, 6-8 

 mic., hyaline, smooth. 



Fig. 665. 



Polyporus leucospongia. 



This is a remarkable species readily known by its very soft sur- 

 face flesh, which is so soft that to the touch it is like a piece of cotton. 

 It occurs on spruce in the mountains of California, and was first sent 

 to Europe by Harkness. His specimens were distributed by Ellis 1104 

 and Rabenhorst 3432, hence found in most museums. They write 

 Cooke's name after Polyporus leucospongia, though Cooke referred it 

 to Polyporus labyrinthicus (which no one knows) and never took the 

 trouble to change his label. Outside the Harkness collections, we have 

 seen but two specimens, one from Mrs. Whetstone, Minnesota, which 

 we refer here, though with some doubt, and a collection from Cuba, 

 Underwood, which was called Polyporus altocedronensis but is the 

 same as Polyporus leucospongia on comparison. Since above was 

 in type Overholts found the plant abundantly in Colorado. 



Compare altocedronensis. 



SECTION 87. CONTEXT, WHEN DRY, SPONGY AND LIGHT. 

 A. Pores large, sinuate. 



POLYPORUS OBTUSUS (Fig. 666). Pileus sessile, large, often 

 six inches or more in diameter. Surface fibrillose, hirsute, rough, soft, 

 no distinct crust. Context (when dry) pale yellowish white, soft, 



323 



