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..
Polyporus lucidus (Leys.) Fr. [Fomes lucidus (Leys.) Fr.] - This species is a very striking one because of the bright red or chestnut color, the hard and brittle crust over the surface of the cap, which has usually the appearance of having been varnished. It grows on trunks, logs, stumps, etc., in woods or groves. The cap is 5-20 cm. in diameter, and the stem is 5-20 cm. long, and 1-2 cm. in thickness. The stem is attached to one side of the pileus so that the pileus is lateral, though the stem is more or less ascending.
The cap is first yellowish when young, then it becomes blood red, then chestnut color. The stem is the same color, and the tubes are not so bright in color, being a dull brown. The substance of the plant is quite woody and tough when mature. When dry it is soon attacked and eaten by certain insects, which are fond of a number of fungi, so that they are difficult to preserve in good condition in herbaria without great care.
The surface of the pileus is quite uneven, wrinkled, and coarsely grooved, the margin sometimes crenate, especially in large specimens. Figure 188 represents the plant growing on a large hemlock spruce stump in the woods. The surface character of the caps and the general form can be seen. This photograph was taken near Ithaca, N. Y.
Polyporus applanatus (Pers.) Fr.[Fomes applanatus (Pers.) Wallr.] - This plant is also one of the very common woody Polyporaceae. It grows on dead trunks, etc., and sometimes is found growing from the wounds of living trees. It is very hard and woody. It has a hard crust, much harder than that of the Polvponis lucidus. The surface is more or less marked by concentric zones which mark off the different years' growth, for this plant is perennial. At certain seasons of the year the upper surface is covered with a powdery substance of a reddish brown color, made up of numerous colored spores or conidia which are developed on the upper surface of this plant in addition to the smaller spores developed in the tubes on the under surface.
The plant varies in size from 5-20 cm. or more in diameter, and 1-10 cm. in thickness, according to the rapidity of growth and the age of the fungus. The fruiting surface is white, and the tubes are very minute. They scarcely can be seen with the unaided eye. Bruises of the tubes turn brown, and certain "artists" often collect these plants and sketch with a pointed instrument on the tube surface. For other peculiarities of this plant see page 15. The age of the plant can usually be told by counting the number of the broader zones on the upper surface, or by making a section through the plant and counting the number of tube strata on the lower surface of the cap at its base.
Polyporus leucophjeus Mont., is said to differ from this species in being more strongly zonate, and in the crust being whitish instead of reddish brown.