Description: The fungus normally exists unseen, in the form of a mass of threadlike vegetative cells called a mycelium, inhabiting rotting wood; only when suitable environmental conditions of temperature, moisture, and nutrient availability are achieved does the fungus produce the reproductive structures known as fruit bodies, or mushrooms. The cap of the fruit body is kidney- or clamshell-shaped, convex to roughly flat, with dimensions of 1.2 to 3.2 cm (0.5 to 1.3 in) by 1.2 to 2.5 cm (0.5 to 1.0 in). The edges of the caps are scalloped with small rounded teeth, and curved slightly inward. The cap surface is dry, with a pattern of block-like areas similar to cracked dried mud; the surface is also covered with small fine hairs that give it a somewhat woolly consistency. It may have several concentric ridges or zones. Fresh fruit bodies range in color from yellowish-orange to buff to cinnamon; when dried they may be various shades of tan, brown or clay. The faded colors of dried fruit bodies tend to revive when moistened. On the underside of the cap, the gills are narrow and spaced closely together, often forked, buff-colored, and with numerous interconnecting cross-veins. Holding the cap in position is a stem that is 0.6 to 1.2 cm (0.2 to 0.5 in) long by 0.3 to 0.8 cm (0.1 to 0.3 in) thick, and has an off-center attachment to the cap, either at or near the cap side. The dull-white stem is covered with minute silk-like fibers, and is narrower at the base where it attaches to the substrate. Fruit bodies do not have any distinctive odor. The flesh is thin and tough, and dark yellow-brown to cream-colored.