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

STROBILOMYCES

391

Tubes 12-15 mm deep, gray or white at first, becoming dark gray,
when injured staining reddish then black, adnate to somewhat decurrent
or slightly depressed around the stipe; pores angular, usually sublamellate near the stipe, when mature gray, staining reddish then black when
injured; tubes when broken downward splitting rather than separating.
Stipe 5-12 cm long, 12-25 mm thick near apex, solid, subcylindric
or enlarged downward, rarely enlarged upward, surface gray to concolorous with the pileus, apex unpolished, striate with longitudinal veins
extending down from the walls of the tubes, base tomentose, midportion covered by a thick woolly sheath from the copious soft veil which
leaves an annular zone or two to several belts lower down when it
breaks, context reddening and finally black when injured.
Spore print black; spores 9.5-15 X 8.5-12 pu, covered entirely by a
complete network of lines to form a reticulum, the ridges up to
0.3-1.7 M high to almost entirely imbedded, the wall rather thick, with a
more or less distinct germ pore, buffy brown with deeper brown ornamentation as revived in KOH.
Basidia 30-58 X (7.5) 10-18 JI, 4-spored. Pleurocystidia numerous,
17-90 X 8-26 Mu, clavate, mucronate-apiculate to more or less fusoid-ventricose, occasionally containing a brown drop when very young, later
brown throughout.
Tube trama with a mediostratum of floccose hyphae with tubular
to vesiculose cells, hyphae diverging from the central strand to the subhymenium. Pileus trichodermium of elements with cells 20-88 /I long,
cylindric or slightly constricted at the septa, the terminal members often
slightly attenuate toward the apex but always rounded, 7-18 j wide.
Clamp connections absent.
Habit, habitat, and distribution.-Solitary to scattered under hardwoods, usually under oak, or in mixed conifer and hardwoods; common
but not found in quantity, summer and fall throughout the state.
Observations.-Unfortunately, there is almost unanimous opinion
that, though not poisonous, this species has little to recommend it for
the table. It is one of the easiest to learn to recognize at sight-seeing it
once is usually enough. Because of its shaggy appearance and dull color
it has been nicknamed the "Old Man of the Woods."
Material examined.-Barry: Mazzer 4067. Cheboygan: Shaffer
1585; Smith 38205, 63109, 63021; Thiers 3606, 3608, 3760, 3831,
4320. Emmet: Thiers 4157, 4266. Gratiot: Potter 3551, 3534, 7597,
7978, 8394, 12878, 13156, 13352. Livingston: Homola 883, 1924;
Hoseney 216, 502; Smith 72722, 72782. Luce: Smith 37487, 41773;
Walsh 307. Montcalm: Potter 10095. Ontonagon: Peters 1129.