The boletes of Michigan, by Alexander H. Smith and Harry D. Thiers.

TYLOPIL US

115

Basidia 4-spored, 8-11 X 17-25 p, clavate, hyaline. Pleurocystidia
abundant, 40-67 X 9-15 /, subventricose-rostrate to subfusoid, apex
acute, hyaline in KOH but content showing in the broad part as a large
(8-12,) globule reminding one of the content of a chrysocystidium as
revived in KOH, in Melzer's the globule disappearing but reddish pigment globules 2-8, in diameter are present, the latter are also scattered
through some hyphae of the hymenophore or hymenial layer. Context
hyphae yellowish to hyaline in Melzer's but scattered reddish pigment
globules 2-8 /L in diameter present in some.
Pileus cutis of appressed hyphae 4-9 p wide. The content reddish
brown to yellowish in KOH and darker in Melzer's with some small
globules present in the latter as revived in Melzer's; end-cells tubular
with blunt apex; in mounts in Melzer's there is much extraneous granular material in the layer. Clamp connections absent.
Habit, habitat, and distribution.-Solitary on sand under pine,
Marquette, September 21, 1965, Mrs. Ingrid Bartelli (Smith 72709).
Observations.-This variety is distinguished by the reddish pigment
globules in mounts of the hymenophore in Melzer's, in the large globule
in the pleurocystidia as revived in KOH, and the terrestrial habitat
among lichens and moss on sandy low soil under pines. Smith 72805
was found on sphagnum in a spruce bog in Washtenaw County. It also
belongs here and indicates a generalized habitat for the variety.
Stirps RUBROBRUNNEUS
51. Tylopilus rubrobrunneus Mazzer & Smith
Mich. Bot. 6:58. 1967
Illus. Pls. 55-59.
Pileus 8-20 (30) cm broad, broadly convex expanding to nearly
plane or at times the disc slightly depressed, margin inrolled at first;
surface dry and unpolished, at times areolate in age (in dry weather);
color when young dark violaceous-brown to chocolate, slowly changing
to deep vinaceous-brown and finally a dingy cinnamon in age ("dark
livid-brown" to "dark vinaceous-brown" to "natal-brown" to "armybrown" or "Sayal-brown"). Context white, firm, taste very bitter, odor
not distinctive, with FeSO4 vinaceous-buff, in KOH no reaction to merely pallid yellow or vinaceous-buff near cuticle, borders of larval tunnels
stained olivaceous.
Tubes 1-2 cm deep, adnate, becoming depressed around the stipe,
when young avellaneous and slowly becoming whitish before being