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

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THE BOLETES OF MICHIGAN

mostly with colored content. Caulocystidia mostly fusoid-ventricose with
proliferated neck, 50-120 X 10-20 iu, flexuous and many branching once
but lacking a cross wall at the base of the neck, many appearing to be
flexuous hyphal end-cells with only a slight basal or subbasal inflation,
both types intergrading, smooth, thin-walled, hyaline to bister when revived in KOH and globules tending to form in some. Caulobasidioles rare
and intergrading with caulocystidia. Caulobasidia mostly 2-spored, usually with yellow-brown content when revived in KOH.
Tube trama of hyaline thin-walled, smooth hyphae with a subfloccose central strand and a diverging subgelatinous lateral band of
hyphae extending into the subhymenium which is cellular near the tube
mouths but hyphal near the pileus trama. Pileus trichodermium very
compact, composed of elements in which the 2-4 distal cells in each
filament are inflated to 10-30,u and are subglobose, walls thin and
smooth, content yellow in KOH and paler bister in Melzer's but no
pigment globules forming. Context of thin-walled hyphae dingy
yellowish revived in KOH or in Melzer's, cells inflated to 10-20 u. Clamp
connections absent.
Habit, habitat, and distribution.-Scattered under blue beech
(Carpinus caroliniana) on low ground; known from the southeastern part
of the state.
Observations.-The yellow pileus, the cellular cuticle, the KOH reaction of the cells of the trichodermium when fresh, the yellow tint over
most of the stipe in age, the color changes in the stipe apex when cut,
and the proliferating caulocystidia as a combination distinguish this
species.