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

SUILL US

45

9. Suillus tomentosus (Kauffman) Singer, Snell, & Dick
Mycologia 51:570. 1960
Boletus tomentosus Kauffman, Pap. Mich. Acad. Sci. Arts & Letters 1:117. 1921.
Boletus hirtellus var. mutans Peck, nom. nud.
Suillus hirtellus var. mutans (Peck) Snell, Lloydia 7:23. 1944.
Xerocomus lenticolor Snell & Dick, Mycologia 52:448. 1960.
Illus. P1. 13.
Pileus 5-10 (15) cm broad, obtuse to convex, becoming broadly
convex, the margin at first incurved somewhat and rather coarsely
tomentose at first, gradually glabrescent; surface at first tomentosefloccose to squamulose overall but gradually glabrescent, the tomentum
and squamules grayish, viscid beneath the tomentose-fibrillose layer;
ground color evenly pale clear yellow to pale orange-yellow. Context
thick (8-15 mm), pallid to yellow but paler than the pileus surface,
changing slowly to blue or greenish blue when cut or bruised, odor
none, taste slightly acid to mild.
Tubes 1-2 cm deep, pale dingy yellow becoming dingy olive-yellow
and staining dingy greenish blue when injured, adnate to decurrent, rarely depressed around the stipe; pores bister to dark dingy cinnamon or
vinaceous-brown when young but slowly becoming dingy yellow, small
(about 2 per mm), staining bluish when injured, at least in age.
Stipe (3) 5-10 (12) cm long, 1-2 (3) cm thick at apex, equal or
clavate, solid, yellow within but paler than pileus surface, staining greenish blue slightly when cut; surface concolorous with pileus or more
orange, glandular dotted to glandular-punctate overall, no veil remnants
adhering and no evidence seen that the tomentum of the pileus actually
represents the remains of a veil.
Spore deposit dark olive-brown very slowly changing to dull cinnamon on drying; spores 7-10 (12) X 3-4 (5),u, smooth, pale yellowish
in KOH, in Melzer's yellowish to pale tan, narrowly inequilateral in
profile view (some swaybacked), obscurely fusoid to elongate-ovate in a
face view.
Basidia 4-spored, 26-34 X 5-8 u, yellowish in KOH and in Melzer's,
clavate. Pleurocystidia typically in bunches and at the level of the
hymenium the cluster surrounded by brown incrusting material (when
revived in KOH), when fresh hyaline to pale vinaceous-brown in KOH;
individual cystidia 30-46 X 7-10 u, subcylindric to narrowly clavate or
narrowed to a blunt apex, often with incrusting debris, content hyaline
to dingy yellow-brown when revived in KOH. Cheilocystidia similar to
pleurocystidia, very numerous and tube dissepiments often with copious