The North American species of Pholiota, by Alexander H. Smith and L. R. Hesler.

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The North American Species of Pholiota

9. P. squamulosa-lacking a pore. Pileus cutis not Phaeomarasmiuslike.
10. P. curcuma var. lanatipes-pore present; cuticle like that of
Phaeomarasmius.
11. P. minutula-apex of spore truncate from pore; pileus cuticle
of encrusted appressed tubular hyphae.
12. P. murrillii-pore minute. Pileus cuticle a trichodermium but
hyphae not strongly encrusted or dark brown in KOH.
13. P. pseudolimulata-apical pore present; pileus cuticle a trichodermium with smooth to encrusted hyphal walls.
14. P. corticola-spore with a "callus." Pileus cuticle a tangled turf
of brown encrusted hyphae.
15. P. cyathicola-no germ pore; cutis not like Phaeomarasmius.
16. P. punicea-no pore. Cuticle + as in P. confragosa.
17. P. canescens-pore minute; pileus cuticle somewhat Phaeomarasmioid.
Of the second group eleven have spores with germ pore, and in one
it is broad enough to cause the spore apex to be somewhat truncate.
Counting all the species with a pore and a cuticle of the type Singer
admits as characteristic of Phaeomarasmius, we have ten species. For the
known North American species witi central stipes, tlen, it is clear that
the Phaeomarasmius type of pileus cuticle is more frequently correlated
with a germ pore at the spore apex than not-by a score of two to one.
On this basis the correlation of lack of a germ pore with the presence of
a Phaeomarasmioid pileus cuticle as a feature distinguishing Phaeomarasmius as a genus is best abandoned.
The nature of the epicutis of the pileus is such that its features do
not lend themselves as well to tabular presentation as does the presence
or absence of a germ pore at the apex of the spore. Singer has raised the
point of the meaning of a typical trichodermium as against appressed
hyphae in fascicles with the ends ascending. The problem of using the
presence of a trichodermium as a generic character in this instance cannot
be considered independently from the problem of the origin of such an
epicutis.
If a parallel situation may be regarded as of some value in indicating
the direction of evolution we may review the situation in Pluteus where
the P. cervinus complex (Section Pluteus) contains species with a cutis
of tubular hyphae (including the end-cell). In other words this cutis, as
regards hyphal differentiation, must be regarded as primitive, for the
primitive hypha generally in Basidiomycetes is of this type. Smith (unpublished data) has been able to observe all degrees of hyphal differentiation starting with the enlargement of the hyphal end-cells to a somewhat cystidioid condition, and a general shortening of the cells in the
cuticular hyphae. These cystidioid end-cells have a tendency to be somewhat ascending either singly or in fascicles, and as this development
progresses a condition is approached which is used to recognize section