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 Polyporaceæ. 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 Polyporus 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 leucophæus Mont., is said to differ from this species in being more strongly zonate, and in the crust being whitish instead of reddish brown.
Polyporus fomentarius (L.) Fr. [Fomes fomentarius (L.) Fr.,] is hoof-shaped, smoky in color, or gray, and of various shades of dull brown. It is strongly zoned and sulcate, marking off each year's growth. The margin is thick and blunt, and the tube surface concave, the tubes having quite large mouths so that they can be readily seen, the color when mature being reddish brown. Sections of the plant show that the tubes are very long, the different years' growth not being marked off so distinctly as in P. applanatus and leucophæus. The plant grows on birch, beech, maple, etc. The inner portion was once used as tinder.
Polyporus pinicola (Swartz.) Fr. [Fomes pinicola (Swartz.) Fr.] occurs on dead pine, spruce, balsam, hemlock spruce, and other conifers. The cap is about the width of the F. applanatus, but it is stouter, and does not have the same hard crust. The young growth at the margin, which is very thick, is whitish yellow, while the old zones are reddish. The tubes are yellowish, and sections show that they are in strata corresponding to the years' growth. Polyporus igniarius (L.) Fr. [Fomes igniarius (L.) Fr.] is a black species, more or less triangular, or sometimes hoof-shaped. The yearly zones are smaller, become much cracked, and the tubes are dark brown. One of these plants which I found on a birch tree in the Adirondacks was over 80 years old.
The genus Merulius has a fruiting surface of irregular folds or wrinkles, forming shallow, irregular pits instead of a deeply honey-combed surface. Merulius lacrymans (Jacq.) Fr., the "weeping" merulius, or "house fungus," often occurs in damp cellars, buildings, conduit pipes, etc. It is very destructive to buildings in certain parts of Europe (see Figs. [189], [190]). Merulius tremellosus Schrad., is very common in woods during autumn. It is of a gelatinous consistency, and spread on the under surface of limbs or forms irregular shelves from the side (see Figs. [191], [192]).