Stinkhorn

Sometimes called the witch's egg,[5] the immature stinkhorn is whitish or pinkish, egg-shaped, and typically 4 to 6 cm by 3 to 5 cm
On the outside is a thick whitish volva, also known as the peridium, covering the olive-colored gelatinous gleba. It is the latter that contains the spores and later stinks and attracts the flies; within this layer is a green layer which will become the 'head' of the expanded fruit body; and inside this is a white structure called the receptaculum (the stalk when expanded), that is hard, but has an airy structure like a sponge