Conocybe lactea - Dunce Cap
Common lawn mushroom in Ontario - edibility unknown but not reported as poisonous.
Caps are 10-30 mm across, conic to bell-shaped, dry to moist, smooth or radially-wrinkled, and tan to cream or almost white. Flesh is thin and white. Stalks are up to 10 cm tall, slender, and minutely hairy.Gills are attached, and whitish becoming rusty. Spore prints are rust-brown. Common and widespread, it fruits on lawns and is recognized by its pale, conical cap and rusty gills.