CONTEXT AND PORES WHITE OR PALE. 



POLYPORUS FUMOSUS (Fig. 647). Pileus thin, smooth, with 

 dull, soft surface. Context, when dry, hard, firm, but brittle; white 

 when fresh, darker when dried. Pores small, round, irregular, white at 

 first, but becoming fuliginous, or dark, in drying. Spores 1]/2. x 5 mic. 



Fig. 647. 



Polyporus fumosus. 



Polyporus fumosus is quite a frequent plant, usually on willow. 

 It is the same, in fact, as Polyporus salignus, with small pores. When 

 it is in its prime, and growing, it is white; but on drying it turns more 

 or less smoke colored. It is often confused with Polyporus adustus, 

 and many specimens of Polyporus adustus in the museums are labeled 

 as being Polyporus fumosus. Dried specimens may be confused some- 

 times, but the difference is marked in the fresh plant. Polyporus 

 adustus has deep, smoke colored pores when growing; Polyporus 

 fumosus has white pores, turning smoky in drying, but when dry 

 rarely deep enough in color to be confused with Polyporus adustus. 

 With Polyporus salignus, however, the case is different. It is the 

 same plant as Polyporus fumosus, with larger pores. When growing 

 white, it is usually called Polyporus salignus. In drying or after it 

 turns "smoky" it becomes Polyporus fumosus. When fresh, Polyporus 

 fumosus has a pleasant odor, as noted by Persoon. 



Compare apalus, cineratus, demissus, pallescens, pelleporus, rhinocephalus, simulans, sub- 

 simulans, terebrans. 



POLYPORUS SALIGNUS. This in the original idea was a white plant grow- 

 ing on willow, the other characters the same, but with large, sinuate pores. In 

 context and color changes it is the same as Polyporus fumosus, and no distinct line 

 can be drawn between it and Polyporus fumosus. 



Compare albus, imberbis, puberula. 



POLYPORUS HOLMIENSIS (Fig. 648). Pileus imbricate, thick, sub- 

 unguliform, hard. Flesh white, with dark lines running through it, also a dark line 

 between the pores and context. Pores and color characters as in Polyporus fumosus, 

 of which it is only a form. 



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