Coprinus atramentarius

Common Name: Tippler's Bane
Description: Cap 3-7 cm high, ovoid at first, then broadly conical when expanded, with the margin irregularly puckered at first, then becoming split; gray to gray-brown; dry, smooth or silky with minute scales or veil remnants, especially near the center.
Habitat: usually in clusters on the ground near rotting or buried wood or in grass. Found widely distributed throughout North America.
Edible: yes, but dangerous because it causes alarming symptoms when taken in conjunction with alcohol.

Source: Mushrooms of North America by Roger Phillips.