The Polyporaceae of North America.—Ill. The Genus Fomes 
By WILLIAM ALPHONSO MURRILL 
The generic name Fomes is usually accredited to Fries, but this 
author never employed it to designate a genus. In Novae Sym- 
bolae, 46, 1851, the genus Polyporus is subdivided into Eupoly- 
porus and Fomes, the latter division being described as follows : 
** Pileus primitus lignoso-induratus (raro molles, plorantes), contextu floccoso inter+ 
texto, crusta rigida obductus, azonus, sed demum concentrice sulcatus. Fwngi peren- 
mes (vulgo stratose), reviviscentes, sed stratum annuum vegetum tantum est.”’ 
In listing species Fries wrote the word /omes in parenthesis 
after Polyporus. 
Gillet (Champ. France, 1: 682. 1878) raised Fomes to generic 
rank and described the group as follows : 
‘*Hyménium poreux ; pores non séparables entr’eux, distincts du chapeau, dis- 
posés par couches stratifiées. Espéces ligneuses-subéreuses, stipitées, dimidiées ou ré- 
supinées, recouvertes d’une croiite dure, épaisse et st. marquée de zénes annuelles 
séparées par des sillons concentriques. Champignons vivaces 4 accroissement in- 
défini.’’ 
Under this genus Gillet lists thirteen species, the first being F- 
marginatus, which is therefore considered its type. Most of the 
remaining species of Homes, as the term is used in Saccardo’s Syl- 
loge, were assigned to this category by Cooke in Grevillea (v. 13 
and 14,1884~85). Karsten was the first to divide generically this 
large group of perennials, which now comprises a half dozen or 
more genera, the name Homes being connected with the natural 
subdivision to which #. marginatus belongs. Karsten’s name 
Fomitopsis, applied to this subdivision in 1881, unfortunately be- 
comes a synonym of Fomes. His names Ganoderma and Elfvin- 
gia, however, hold for other important subdivisions. 
Synopsis of the North American Species 
I. Context white or yellowish. 2. 
Context flesh-colored, pileus often effused or effused-reflexed, flesh-colored, soon 
blackening, tubes round, 3-4 to a mm. 1. F. roseus. 
2. Pileus over 3 cm. broad. Ee 
Pileus less than 3 cm. broad. 8 
3. Pileus encrusted, surface darker than the context. 4- 
Pileus rarely encrusted, surface concolorous with the context. 9. 
225 
