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

Subgenus Plinthogalus

135

County, Michigan, leg. A. H. Smith, 63004 (type, MICH), August 24,
1960.
Observations.-The marginate variety is based on a combination
of features which some might regard as sufficient for classifying it as
a species in its own right, but after studying the variants around L.
lignyotus we decided against this. The known fruit bodies of var.
marginatus grew along with the type variety in the same relatively
small area, but were slightly smaller though within the size range for
it. It was a matter of some interest to us to observe the number of taxa
in this subgenus which possessed marginate gills in relation to (apparently) the lack of development of this character among European
populations.
Material cited.-MAINE: Homola 5587 (MICH); MICHIGAN:
Smith 63004 (type, MICH); Weber 3973 (MICH).
27. Lactarius ruginosus Romagnesi
Bull. Soc. Mycol. France 72: 335, 1956
Lactarius flliginosus var. clitoc:hoides Smith & Hesler, Brittonia 14: 420. 1962.
Illus. Brittonia 14, pl. 21, pl. 22 upper figure. P1. 22; fig. 53.
Pileus 4.5-7 (11) cm, broadly convex to plane and at times sulcate and rimose, more normally less deeply sulcate, often with an obscure umbo in the depression or several obscure elevations, margin
thin, at first narrowly and abruptly incurved, then spreading, often with
short faint marginal grooves (short-sulcate) but often + dentate from
short projections; often bister in color (K 112 but redder, toward 115;
Ridgway xxix, 15" bister), generally only an ochraceous-bister but
going to the color of L. pterosporus, surface at times nearly smooth
and moist, however never dull and matted, but becoming rugosereticulate or undulated (with mounds) over disc, but this feature not
pronounced in age.
Lamellae distant, thick, with numerous lamellulae, decurrent becoming arcuate, pointed in front (near cap margin), broad (3.5-5 mm
rarely to 13 mm), at first clear ochraceous and lacking rose tones, becoming ochraceous-salmon, finally a salmon-ochraceous or orange-ochraceous (yellower than "cinnamon-buff"); edges concolor; pruinose in
age.
Stipe 3-5 cm long, 8-15 mm thick, equal or enlarged near apex,
slightly curved below and tapered near base, more or less bister overall (Ridgway), or paler ochraceous with a darker base, discoloring to
dingy brown (finally spotted or discolored overall in age); surface
smooth, continuous, shining, only in age some striations and reticulation appearing.