Inky Cap

These mushrooms have a nifty way of dispersing their spores: the gills actually digest themselves at maturity, dripping black spore-laden fluid all over the place. This deliquescing process is distinctly different from the normal decay process of most mushrooms, and characterizes the Coprinus genus.

The tallest, mature cap in this photo has already begun to drip its "ink" on the shorter mushrooms around it. It eventually becomes a very messy scene!