Phallus ravenelii

Common Name: Stinkhorn.
Description: Fruiting body 10-16 cm high, 13-15 mm thick; head green to gray-green, granulose, slimy to sticky with an open depression at the top. Odor nauseous to fetis, sometimes detectable several yards away.
Habitat: Usually in a dense cluster in wood debris or sawdust. Widely distributed.
Edible: Nonpoisonous.

Source: Mushrooms of North America by Orson K. Miller, Jr.