SAPROPHYTIC FUNGI OF EASTERN IOWA. 



19 



species is also one classed by Hartig among those specially 

 destructive as parasites on timber trees, and it appears that 

 fungi flourishing on a tree readily infect trees of entirely dif- 

 ferent species. Hartig, LcJirbnch der Pfiaiizcnkraiik/ici/oi, p. 

 88. N. A. F. 915. 



4. Fo.MES FOMEXTARius [Liiiiiceiis) Fn'cs. 



Pileus ungulate-pulvinate, thick, glabrous, remotely concen- 

 tricall}^ sulcate, from sooty canescent, within soft fioccose 

 fulvous; the crust thick, hard and persistent; margin and 

 pores prolonged, the latter minute, distinctly stratose, at first 

 glaucous-pruinose, then rusty. 



This is the type of the genus. The soft context seems 

 from time immemorial to have been used as touchwood, Latin 

 fumes, punk or spunk. Comparison of the last word with 

 the word sponge or even fungus is also interesting. The 

 specific name of the species preceding likewise contains an 

 allusion to the earlier use of such fungi for the development 

 or preservation of fire. The present species is not only the 

 type but is also the most elegant of the series. The smooth 

 surface, the pale ashen hymenium and the even regular pores 

 all combine to make a very handsome fungus. Said to 

 flourish best on species of Fagiis. As beeches do not occur 

 in Iowa we must be content with the smaller more cylindric 

 form that affects the birch. In fact our specimens are all 

 from a single species of the latter tree, Betula -papyracca, 

 occurring in our north-eastern counties only. N. A. F. 1102. 



5. FoxMES APPEANATUS (^Pcrsoou) Wallrotk. 



Pileus dimidiate, flat, somewhat thickened behind, nodose, 

 indistinctly zonate and sulcate, glabrate or pulvinate, at first 

 brown then gray or ashen with a rigid but fragile crust; con- 

 text soft, flocculose; margin tumid; pores very small feniigin- 

 ous the mouths whitish, brown when rubbed. 



Everywhere common on trees of all sorts, extending some- 

 times half a meter in width and one third of a meter in length. 

 In protected situations the sporocarp continues growing many 

 years, adding stratum after stratum each immediately on the 



