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..
This very interesting species was collected at Ithaca, N. Y., on decaying wood, August 4, 1899. The pileus is lateral, shelving, the stem being entirely absent in the specimens found. The pileus is 2-5 cm. broad, narrowed down in an irregular wedge form to the sessile base, convex, then expanded, the margin incurved (involute). The color of the cap is yellow, maize yellow to canary yellow, with a reddish brown tinge near the base. It is nearly smooth, or very slightly tomentose. The flesh is pale yellow, spongy. The gills are orange yellow, 2-3 mm. broad, not crowded, regularly forked several times, thin, blunt, very wavy and crenulate, easily separating from the hymenophore when fresh; the entire breadth of the gills is fluted, giving a corrugated appearance to the side. The spores in these specimens are faintly yellow, minute, oblong, broadly elliptical, short, sometimes nearly oval, 3x1.5-2 µ. The basidia are also very minute. The spores are olive yellow on white paper. The plant has a characteristic and disagreeable odor. This odor persists in the dried plant for several months.
Figure 162 is from the plants (No. 3332 C. U. herbarium) collected as noted above on decaying hemlock logs in woods. A side and under view is shown in the figure, and the larger figure is the under-view, from a photograph made a little more than twice natural size, in order to show clearly the character of the gills. The two smaller plants are natural size. When dry the plant is quite hard.
Plate 53, Figure 162
Paxillus corrugatus. Cap maize yellow to orange yellow, reddish brown near the base; gills orange yellow. Two lower plants natural size; upper one 2 1/2 times natural size. Copyright.
Plate 55. Fig. 1. - Boletus felleus, Fig. 2. - B, edulis, Copyright 1900.