A bracket fungus, a parasite and killer of many types of tree, it is shaped a little bit like the hoof of a horse. It is also called the Tinder fungus because it burns easily, and can be used to start a fire from a spark. Ötzi the Iceman, whose five thousand year old remains were found in an Alpine glacier some years ago, was carrying four chunks of this fungus.
These specimens were growing on the trunk of a tree beside the Smestow Valley LNR railway walk, near the Alpine Way access point. The unnatural brightness of the greens of the moss and ivy leaves in the lower pictures is because I needed to use the on-camera flash to get enough light for the photos.