A week or two ago, I came across this lump of green jelly-like substance in the Wilderness. It was on a dead leaf on the ground just below this slime-covered log:
I suspect that this slime is blue-green algae (Cyanobacteria), possibly a Nostoc sp. In particular, it looks like the amorphous terrestrial form shown at the foot of this page at Down Garden Services.
Photos taken in the Wilderness, Whiteknights Park, Reading University grounds, Reading, UK, on 2010-11-23.