Figure 383.—Stereum sericeum.

Sericeum means silky or satiny; so called from its satin lustre. The plant is very small and easily overlooked, usually growing in a resupinate form; sessile, orbiculate, free, papyraceous, with a bright satin lustre, shining, smooth, pale-grayish color.

The plant grows on both sides of small twigs as is shown in the photograph. I do not find it on large trunks but it is quite common on branches. No one will fail to recognize it from its specific name.

When I first observed it I named it S. sericeum, not knowing that there was a species by that name. I afterwards sent it to Prof. Atkinson and was surprised to find that I had correctly named it.

Stereum rugosum. Fr.

Rugosum means full of wrinkles.

Broadly effused, sometimes shortly reflexed; coriaceous, at length thick and rigid; pileus at length smooth, brownish.

The hymenium is a pale grayish-yellow, changing slightly to a red when bruised, pruinose. The spores are cylindrico-elliptical, straight, 11–12×4–5µ. Massee.

This is quite variable in form, and agrees with S. sanguinolentum in becoming red when bruised; but it is thicker and more rigid in substance, its pores are straighter and larger.