Fuligo septica var flava - a Slime Mould. Slime Moulds were once thought to be fungi but are now generally recognised as Protozoa. They exist as free-living single-celled amoeboid creatures which coalesce into a Plasmodium stage to mate. It is this Plasmodium stage we see here with the "slime" at the bottom and left being the snail-like trail left as the whole mass moves slowly over its food source (a conifer stump in this case). Photographed 4 June 2011