BOLETI OF THE UNITED STATES 75 
composed of several broader radiating lamelle abundantly 
connected by more narrow transverse and anastomosing 
branches or partitions which thus form large angular pores 
whose dissepiments are more or less uneven or dentate on 
the edge. The radiating lamellae are more distinct toward 
the stem, and gradually lose themselves toward the margin. 
In some species they are more clearly seen in the young 
plant than in the adult. The hymenium is to some extent 
separable from the hymenophore, though not easily, but in 
the young plant, at least of one species, I found it insepa- 
rable. The projecting mucros or points, appearing not un- 
like pale scattered hairs, are not, in my opinion, a good 
generic character, for | have observed them in many species 
whose tubes easily separate from the hymenophore and 
from each other and which therefore are genuine Boleti. 
The characters ascribed to the stem are also not of generic 
value and should be omitted if we accept the evidence of 
our American species. In one species, Paxzllus porosus 
Berk., the stem is lateral or eccentric, and by this character 
and by the peculiar radiating structure of the hymenium 
this genus is shown to be intermediate between Paxillus 
and Boletus. It affords a resting place for the species just 
mentioned, for it seemed before to be at home neither with 
the Paxilli nor with the Boleti. The generic diagnosis 
should in my opinion be emended as follows: 
Hymenium lamellis latioribus radiantibus transversé 
connexis ramis angustioribus numerosissimis anastomosan- 
tibus formatum. Tubuli subtenaces, egre ab hymenophoro 
et a se invicem sesedentes, magni, angulati, adnati vel 
subdecurrentes, lutescentes. 
flymenitum composed of broader radiating lamelle con- 
nected by very numerous more narrow anastomosing branches 
or partitions and forming large angular pores. Tubes some- 
what tenacious, not easily separable from the hymenophore 
and from each other, adnate or subdecurrent, yellowrsh. 
