19141 
BURT—THELEPHORACE/E ОЕ NORTH AMERICA. I 197 
Cantharellus, of the Адатсасее. Some species of Corticium must 
be cautiously separated from Меги ия, of the Polyporacee. 
The species of T'remellodendron, Hirneolina, and Setacina were 
formerly distributed among Thelephora, Stereum, and Corti- 
cium respectively, but are now separated from these genera by 
the cruciate character of the basidia,—such basidia as are pres- 
ent in many T'remellacem. АП these connecting genera will 
be included in the present monograph. 
Michenera and Heterobasidium are excluded genera. Lyman 
has shown! that Michenera artocreas B. & C. is only a stage in 
the life history of Corticium subgiganteum B. & C., and that the 
genus Michenera has ceased to be a genus of the Basidiomycetes. 
My own study of the type of Heterobasidium chlorascens Massee, 
which is the type species of the genus, failed to locate any 
basidia whatever. 
Very many Thelephoracee are of great economic importance 
on account of the dry rot induced by the growth of the mycelium 
in sills, floors, mine, bridge, and dock timbers, and other wooden 
structures located in moist, poorly ventilated places. Conio- 
phora puteana is а common species which rots coniferous wood. 
Only a very few Thelephoracee are classed as serious plant 
parasites. Of these the rhizoctonial stage of Corticium vagum 
is the most important. | 
KEY TO THE GENERA 
I. EU-THELEPHOREJE: 
Fructification not containing green lichen gonidia. 
Fructification fleshy or membranaceous, often infundibuliform, with the 
hymenium distinct, continuous, even, ribbed or at length rugose; ba- 
Coo f. s. ee a ae RET UU eS Craterellus 
Fructification submembranaceous, cup-shaped, often pendulous; hymenium 
typically concave, discoid; basidia віпіріе....................... Cyphella 
Fructification consisting of only a fleshy hymenium on the surface of living 
leaves and shoots; Бава вітріе......................... Exobasidium 
Fructification coriaceous or һага..................................... 1 
1. Basidia globose or pyriform, longitudinally cruciately 4-septate or divided 
when mature; fructification erect, clavariform, more or less branched ....... 
Tremellodendron 
1Cultural studies on the polymorphism of Hymenomycetes. Proc. Boston Soc. Nat. Hist. 33: 
151-60. 1907. 
