North American species of Lactarius / L. R. Hesler, Alexander H. Smith.

Subgenus Plinthogalus

157

Melzer's. Stipe cuticle of longitudinally arranged and interwoven
hyphae 4-6, wide with somewhat thickened walls; at surface occur
hyphal ends with thin walls, measuring 30-80 X 4-6 /; rosettes present
in stipe cortex.
Habit, habitat, and distribution.-Under oak, pine, and mixed
shrubs and trees (Chinese tallow, marsh elder, youpon, etc.), on soil
rich in lignin, solitary or a few widely gregarious, rare: near Liverpool, Texas, Hillhouse 160 (type, MICH).
Observations.-Mr. Hillhouse reports finding only 6-7 basidiocarps
per year in the type locality. The odd features of the species are the
color of the spore deposit on white paper, the tendency for the stipe
to branch to produce more than one cap, and the large globose spores
with a ~ reticulate ornamentation. He mentioned that the color of the
spore deposit closely matched the color of the lamellae. Since the color
of the spore deposit is not known for the type of L. eburneus, we
describe Mr. Hillhouse's material as a variety of that species because
of the prominent cheilocystidia, mild taste, spore ornamentation +
1.5 At high, and reddish staining context.
Material cited.-TEXAS: Hillhouse 160 (type, MICH), 269, 270
(all MICH).