1915] 



OVERIIOLTS — STUDIES IN THE POLYPORACEAE 693 



therefore, that we are here dealing with a character that 

 varies with the age of the plants or even varies in different 

 plants of approximately the same age. In other characters 

 the two species are identical. Bearing in mind then the fol- 

 lowing points: (1) Peck's admission concerning his species, 

 (2) the little reliance that is to be placed on odors in at least 

 some of the fungi, (3) the evidence that P. fumosus is some- 

 times fragrant as it grows in Europe, and (4) the variability 

 in the size of the pores in a single collection, we can only con- 

 clude that P. fragrans is at most only a form of P. fumosus 

 and not worthy of a distinct name. 



There are a few other names that need to be mentioned be- 

 fore dismissing this group of species. P. salignus Pers. ex 

 Fries is generally held to be P. fumosus, and Fries ' illustra- 

 tion 1 certainly agrees with the species as it grows in this 

 country. P. Holmiensis Fries, as distributed by Romell, 2 is 

 surely our plant and it is so regarded by Bresadola. P. im- 

 berbis Bull, ex Fries, as represented by Bresadola, is the same 

 plant, but the name was not recognized by Fries in his 

 'Systema Mycologici' and so cannot be used for our plant. 



The following key will aid in distinguishing the four species 

 presented here : 



Pileus rather thin; hymenium black or smoky black; tramal hyphae distinctly 



brown in section 1 



Pileus thicker; hymenium pallid to somewhat smoky; tramal hyphae hyaline 



or nearly so in section If. P. fumosus 



1. Pileus finely tomentose; margin thin, even, sterile below; context firm 



when dry; pores minute; plants slightly, if at all, imbricate. .1. P. adustus 



Pileus adpressedly fibrillose on the margin, usually strigose toward the 

 base; margin thin, crisped or wavy, sterile below; context firm 

 when dry; pores larger and unequal; plants usually closely imbri- 

 cate 2. P. crispus 



Pileus finely tomentose; margin acute but thicker than in the pre- 

 ceding species, even, fertile below; context soft and floccose; pores 

 unequal; plants scarcely imbricate 3. P. Burtii 



1. Polyporus adustus Willd. ex Fries. Plate 23, fig. 8. 



Pilei not much imbricate though somewhat so at times, 

 1-6 X 3-8 X 0.1-0.6 cm., white to smoky white or pale tan, 

 rarely with reddish blotches or zones, finely tomentose to 

 short villous-tomentose, zonate or azonate; margin thin, even, 



1 Ic. Hym. 2: pi. 181. 



2 



Fung. Scand. 11. 



