Hae BULLETIN OF THE NEW YORK STATE MUSEUM 
represented by scanty material in an Pas Leon condition 
have been omitted. 
The genera Boletinus and Strobilomyces are not very 
sharply distinguished from the genus Boletus, and Professor 
Fries did not attribute generic value to them. But one 
character ascribed to both of them in Sylloge Fungorum 
conflicts to such an extent with the Friesian description of 
the genus Boletus that it may be well to recognize them as 
distinct. This distinctive character is expressed in the fol- 
lowing 
Synopsts of the Genera 
Tubes easily separable from the hymenophore and from each 
(O01 PY SH lines: BA aa en RE Se Dre Reeth Ee al AE OI Wan ms GA, Cn Boletus. 
ae not easily separable from the innpsnvememlbart REO boGO8 yt 
1. Hymenium with a perceptible radiating structure... Boletinus. 
1. Hymenium without a perceptible radiating structure. Strobilomyces. 
BOW Ean Seiexwerns: 
Hymenophore not even (as in Boletus) but extended in 
mucros descending like a trama among the tubes. Tubes 
not easily separable from the hymenophore and from each 
other. Stem annulate, hollow, spores pale yellowish. Syl- 
loge Vol. VI, p. 51. 
This genus was founded by Kalchbrenner on Boletus cave- 
pes Opat., the only European representative) of) 1b) isis 
diagnosis differs slightly from the one quoted in saying that 
the tubes are not separable from the hymenophore nor from 
each other, and that the stem is central and the fungus 
fleshy and putrescent. Fries, who apparently had not seen 
this fungus, says, with characteristic sagacity, that from the 
character given, it constitutes a peculiar genus whose whole 
appearance is that of Boletus and whose limits are not yet 
defined. 
In the United States there are several species which evi- 
dently should be referred to this genus. Bya study of them 
it becomes clear that Fries was right in his assertion and 
that a very important generic character has been overlooked. 
This is the radiating structure of the hymenium which is 
