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

86 The North American Species of Pholiota
dextrinoid spores. The basidiocarps show a strong superficial resemblance
to those of Galerina autumnalis but spores and cystidial features separate
them sharply. It is not related closely to P. mutans though one might get
this impression from comparing descriptions. The caulocystidia vary from
simple projecting hyphal tips to cells resembling the cheilocystidia.
32. Pholiota davidsonii sp. nov.
Illustrations: Text figs. 47-48.
Pileus 2-3 cm latus, late convexus, luteofulvus, glaber viscidus. Caro
luteola. Lamellae subdecurrentes, brunneae confertae, latae. Stipes 2-3
cm longus, 3-5 mm crassus, obscure pallidus, sursum pruinosus, deorsum
fibrillosus. Sporae 8-10(12) x 4-5(6-6.5) it. Pleurocystidia desunt. Cheilocystidia 20-32 x 5-7 Ai, subcylindrica vel subventricosa, tenuitunicata.
Caulocystidia clavata, 8-15 i diam. Specimen typicum in Herb. Univ.
Mich. conservatum est; legit. prope Estes Park, Colorado, (Rocky Mts.
Nat'l. Park), Ross Davidson 112.
Pileus 2-3 cm broad, convex, slightly hemispheric, yellowish tawny,
glabrous, slightly viscid when wet. Context thick on disc, thin on margin.
tinged yellowish.
Lamellae adnate-subdecurrent, brown (color when young not recorded), close, broad, edges whitish and minutely fimbriate.
Stipe 2-3 cm long, 3-5 mm thick, dingy-pallid, apex pruinose, elsewhere sparsely fibrillose, equal. Veil white, rather heavy-arachnoid but
not membranous, appendiculate, fugaceous.
Spores 8-10 (12) x 4-5 (6-6.5),i, smooth, dark rusty brown in KOH,
a paler tawny-cinnamon in Melzer's sol., smooth, with a distinct apical
germ pore which in the giant spores causes the apex to appear truncate;
elliptic to ovate in face view, somewhat inequilateral in profile; wall
0.3-0.5 ut thick (estimated).
Basidia 25-32 X 6-8 iu, 4-spored or rarely 2-spored (large spores seen
in diads.), hyaline in KOH and yellowish in Melzer's reagent. Pleurocystidia none. Cheilocystidia very inconspicuous, 20-32 x 5-7 iL, buried
in the hymenium of the gill-edge, subcylindric to ventricose or a few
fusoid-ventricose, thin-walled, hyaline in KOH, content homogeneous.
Caulocystidia present as clavate end-cells of stipe hyphae, 8-15 Px diam.
and variable in length, hyaline, walls thin and smooth, content homogeneous.
Gill trama of floccose hyphae 5-10 /u diam. (gills all young) somewhat interwoven to parallel; walls thin, smooth and hyaline to yellowish revived in KOH; subhymenium of cellular construction and not
gelatinous, the cells 4-8 aL diam. Pileus cutis a layer of hyphae 3-6 Fu
diam. with incrusted walls, the zone refractive in KOH indicating presence of slime but individual hyphae clearly delimited; hypodermial zone
of more deeply colored incrusted hyphae. Context hyphae hyaline to