Xylaria carpophila  

Stromata 2-4 (-6)  cm long and 1-2 µm diam., solitary or in small clusters, filiform, rarely branched, often irregularly curved, hairy at the base and sometimes throughout, black, white-tipped when producing conidia.
Teleomorph: ascomata perithecia, forming protuberant mounds in fertile stromata. Ascospores 10-16 x 4-5 µm, dark brown, with a straight germ slit running almost the entire length of the spore.