Fig. 45. Polyporus sulphureus. i, an entire fungus about ore- 

 quarter nat. size ; 2, section through the same, showing the thick, 

 fleshy pileus at a, and the tubes, which have the cavity lined with 

 the hymen ium, or spore-bearing surface, at b\ 3, a basidium bearing 

 four spores, x 300. 



