This section is from the book "Studies of American Fungi: Mushrooms, Edible, Poisonous, Etc.", by George Francis Atkinson. Also available from Amazon: Studies of American Fungi: Mushrooms, Edible, Poisonous, Etc..
The smoky or dingy lactarius occurs in woods and open grassy places. It is widely distributed. The plants are 4-7 cm. high, the cap 3-5 cm. broad, and the stem 6-10 mm. in thickness. The light smoky color of the cap and stem, the dull yellowish white color of the gills, and in old plants the wavy margin of the cap make it comparatively easy to recognize the species.
The pileus is thin, at first firm, becoming soft, convex, then plane and often somewhat depressed in the center, usually even, dry, the margin in old plants crenately wavy, dull gray or smoky gray in color, with a fine down or tomentum. The gills are adnate, distant, more so in old plants, white, then yellowish, sometimes changing to salmon color or reddish where bruised. The spores are yellowish in mass, faintly yellow under the microscope, strongly echinulate or tuberculate, globose, 6-10 µ. The stem is usually paler than the pileus, firm, stuffed. The milk is white, slowly acrid to the taste.
Lactarius fuliginosus. Cap and stem smoky, cap usually not wrinkled; gills white, then light ochre, distant (natural size). Copyright.
Figure 120 is from plants (No. 3867, C. U. herbarium) collected at Blowing Rock, N. C, during September, 1899.