Yellow brain or Witches' butter

The fruiting body is 3-10 cm across, gelatinous, wavy and folded, with irregular lobes and folds, like a wrinkled brain or a lump of yellow jelly pudding. It's attached by its side or back to the substrate, with no distinct stem. In wet weather it's soft, jelly-like, glossy and moist; in dry weather, old ones turn wrinkled and hard. The colour is bright yellow, lemon yellow or orange-yellow, deepening to a richer orange with maturity.

Fresh fruit bodies are jelly-like and rubbery, button-shaped or pressed flat at first and attached at a narrow point, sometimes with a short stalk-like base, then top-shaped or almost cup-shaped, usually 1 to 5 cm across. They grow singly or in groups and sometimes partly fuse.

They're dark grey to brownish grey, later brownish black, almost black. The upper surface is uneven and dotted with small black pegs.

The spore-bearing surface covers the outside of the wavy lobes. It's smooth, with no gills, pores or spines. Spore print white.

The spores form on the pegged upper surface. The underside is sterile and felty, covered in dense blackish hairs.

The spore print is white.

No stem. The fruiting body is attached to the substrate by its side or back edge (sessile).

There's no true stem: it's attached to the bark at a narrow point or by a short base.

The flesh is gelatinous, soft in wet weather and hard in dry weather. It's transparent to translucent and yellowish, and doesn't change colour when cut. No distinct taste (neutral, jelly-like); the smell is faint and neutral.

The flesh is jelly-like, soft to fairly firm, watery olive-grey to greyish brown. In dry weather it shrinks to a thin black crust, then swells again after rain.

Faint, neutral, nothing distinctive.

The smell is indistinct.