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

BOLETUS

363

feature in assigning future collections to B. gertrudiae. The species needs
to be redescribed from such fresh material. We suspect that it will be
found to be a readily recognizable species once properly described on a
modern basis. To date we have not recognized it in the Michigan flora.
Stirps SEPARANS
197. Boletus separans Peck
Bull. Buff. Soc. Nat. Sci. 1:59. 1873
Boletus edulis subsp. separans (Peck) Singer, Amer. Midi. Nat. 37:26, 1947.
Boletus nobilis Peck, Bull. N. Y. State Mus. 94:48. 1904.
var. separans
Illus. Figs. 99-101; P1. 118 (right).
Pileus 6-15 (20) cm broad, convex with a bent in margin becoming
broadly convex or with a low broad umbo; surface dry and unpolished
or when wet somewhat tacky, glabrous in age; dark dull red to liverbrown- or bay-brown, with an ochraceous undertone near the margin.
Context pallid, unchanging, reddish near the cuticle, odor and taste mild
in fresh state.
Tubes adnate becoming depressed, whitish, slowly dull yellowish
to dingy ochraceous (not olivaceous), unchanging; pores stuffed and
white when young, becoming pale yellow, not staining blue, 1-2 per
mm, round or nearly so.
Stipe 6-15 cm long, 10-25 mm thick, enlarged downward, finely
reticulate as in B. edulis; concolorous with or paler than the pileus,
glabrous, base whitish at first, white within.
Spores 12.5-16 X 3.5-4.5 j, narrowly subfusiform in face view, in
profile narrowly inequilateral, smooth-walled and wall only slightly
thickened, yellow in KOH, yellow to ochraceous-tan in Melzer's (no
fleeting-amyloid reaction present), some with an orange-brown content
as revived in Melzer's.
Basidia 4-spored. Pleurocystidia none or present only as pseudocystidia imbedded in the hymenium. Tube trama gelatinous, more or less
divergent from a central strand. Cuticle of pileus a tangled trichodermium with end-cells clavate to fusoid-ventricose and 40-80 X
12-18 g, content yellow to hyaline in KOH, in Melzer's the layer reddish
but the content of individual cells ochraceous; laticiferous elements in
the context fairly numerous. Clamp connections absent.