This is Fuligo septica, an organism with the lovely common name, Dog Vomit Slime Mold. Again, common names can be misleading. Slime Molds are not molds at all. Instead, they are protists. Fuligo septica is a plasmodial slime mold. Instead of being made up of many cells, each with one neucleus, this is one giant cell membrane that contains many, many nuclei. A truly strange and amazing organism.