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

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North American Species of Lactarius

does occur, the significance, taxonomically, may still be open to question. As far as olive and brown are concerned, the former may change
to the latter and we cannot now be sure that both are not simply part
of a + continuous reaction-one which may not always progress to completion depending on the condition of the basidiocarp. However, in
some collections brown stains develop in a short time and are not preceded by olive tones. In summary, we have tried to bring the taxonomic problems involved in this group into focus so that they can be
studied from the background we have established.
L. kauffmanii, as presently described, is distinguished by: (1) the
dark to blackish brown slimy pileus; (2) slimy ~ vinaceous to tan
stipe; (3) more or less pale vinaceous lamellae when young staining
olive to gray and finally brown; (4) large size; and (5) the "in between" color of the spore deposit.
Dr. Calvin Henry Kauffman collected this species on his expedition to Lake Cushman, Washington, in 1915. We take pleasure in dedicating it to him.
Material cited.-CALIFORNIA: Smith 56278, 56532; Thiers 8312,
21335, 21438 (all SFSC); IDAHO: Smith 54534 (type, MICH), 74011,
82049, 82337, 82342, 82382, 82411, 82413, 82414, 82416, 82417, 82418,
82419, 82420, 82447, 82448, 82450, 82451, 82579, 82624, 82627, 82745,
82752, 82831, 82833, 83015, 83016, 83017, 83062, 83063, 83064, 83065,
83066, 83155, 83162; MICHIGAN: Weber 4032 (MICH); OREGON:
Kauffman, October 10, 1922 (MICH); Smith 79152, 79186, 79247, 82697,
82698, 82702, 83728, 83729, 83769; WASHINGTON: Kauffman, October 10, 1915 (MICH); Smith 16897, 17544, 29481, 31189, 31212,
40476, 40910, 40913, 47640, 48874, 77062, 77067, 82082; WISCONSIN: Weber 4262, 4264 (all MICH).
Canada. BRITISH COLUMBIA: Harrison, September 3, 1966
(MICH).
125a. Lactarius kauffmanii var. sitchensis var. nov.
Illus. P1. 55.
Pileus (3)6-15 cm latus, late convexus demum plano-depressus,
glaber, viscidus, atrovinaceus demum ligno-brunneus vel sordide luteo-brunneus, acer; latex albolacteus, acer, constans; lamellae confertae, adnatae vel decurrentes, albidae demum pallide ochraceae,
leviter brunneo-maculatae; stipes 5-9 cm longus, (0.6)1-2 cm crassus,
viscosus, subvinaceus vel pallidus, rare scrobiculatus; sporae in cumulis luteae, 7-9(10) X 6-7.5(8) u. Specimen typicum in Herbarium
University of Michigan conservatum; legit prope Neskowin Creek,