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

470

North American Species of Lactarius

"2nd Type" (from Yaphank). We have not seen the Selkirk collection
and so designate the Yaphank collection as a lectotype.
L. mutabilis is distinguished by its mild taste, zonate pileus before fading, dull brown colors, white to watery white latex and whitish
then yellowish lamellae. In northern specimens the spore deposit is
whitish to cream and in southern material it has been observed to be
Naples-yellow in some collections-indicating, along with the variable
staining pattern, that the species should be studied further. Smith
86093 appears to belong here but the taste was very slowly acrid. The
spore deposit was white.
Material cited.-GEORGIA: Hesler 13959; MICHIGAN: Hoseney
2258 (MICH); Patrick 546 (MICH); Potter 9855, 11107, 11199, 13394,
13505 (all MICH); Smith 4953, 62569, 62923, 64165, 81475, 81477,
81494, 84191a, 84641, 84641a, 86093; NEW YORK: Peck, Yaphank,
September (lectotype, NYS); NORTH CAROLINA: Guravich 507,
548 (all MICH); Hesler 21877, 22045, 22072, 22342, 23180, 24751;
OHIO: Mazzer 7533 (MICH); TENNESSEE: Hesler 11349, 23077,
24532, 26524, 28162; VIRGINIA: Hesler 13959.
Section PSEUDO-AURANTIACI (Hesler & Smith) stat. nov.
Subsection Pseudo-Aurantiaci Hesler & Smith, Brittonia 12: 326. 1960.
Latex weakly yellow when exuded, watery to milk-white but soon
yellowing on exposure, or latex leaving yellow stains on white paper in
drying.
Type species: Lactarius substriatus
Observations.-See section Piperites and subsections Scrobiculati
and Croceini also, for species with yellowing or yellow staining latex.
KEY TO SPECIES
1. Pileus brilliantly colored at first; deep red to orange or bright yellow.......... 2
1. Pileus with duller colors than in above................................. 7
2. Pileus deep red (mahogany-red) at first, often vinaceous-pink when
faded........................................................ 3
2. Pileus scarlet to orange to yellow.................................. 5
3. Spores 6-7.5 X 6-7 g......................... see L. hysginus var. subroseus
3. Spores not as above................................................ 4
4. Pileus cuticle having a basal layer of vesiculose cells; spores 8-10
X 7-8 A............................................ L. subviscidus
4. Pileus cuticle lacking a distinct layer of vesiculose cells under the cuticle;
spores 7.5-9 X 6-7.5 u................................... L. hepaticus
5. Taste mild............................................ see L. splendens
5. Taste at least slightly acrid finally..................................... 6