Phallus impudicus

The common stinkhorn (Phallus impudicus) is a common fungus recognizable for its foul odour and its phallic shape when mature, the latter attribute giving rise to several amusing names in 17th-century England. Occurring mainly in deciduous woods in Europe in summer and autumn, it is a tall white fungus with a slimy green conical cap-like structure. Despite its foul smell, it is not poisonous and is consumed when young in parts of France and Germany.

Taxonomy
Botanist John Gerard called it the "pricke mushroom" or "fungus virilis penis effigie" in his General Historie of Plants of 1597, and John Parkinson "Hollanders workingtoole" or "phallus hollandicus" in his Theatrum botanicum of 1640, while Linnaeus was responsible for the fairly obvious genus name. Its specific epithet, impudicus, is derived from the Latin for 'shameless' or 'immodest'.

Distribution and habitat
Occurring in Europe, the common stinkhorn is most commonly found in deciduous woods from summer to late autumn, though may also be found in conifer woods or even grassy areas such as parks and gardens.

Description
The mature stinkhorn is 10-18 cm (4 - 7 in) tall and 2-3 cm (5/8-1 in) in diameter, topped with a conical 2-4 cm high cap which is covered with a greenish-brown slime termed the gleba. Their method of reproduction is different to many mushrooms, which use the air to spread their spores. Stinkhorns instead produce a sticky spore mass on their tip which has a sharp, sickly-sweet odor of carrion to attract flies. The mature fruiting bodies can be smelt from a considerable distance in the woods, and at close quarters most people find the cloying stink extremely repulsive. The flies land in the gleba and in doing so collect the spore mass on their legs and carry it to other locations. In older fungi the slime is eventually removed, the bare yellowish pitted and ridge surface is exposed. This has a passing resemblance to a morel.

Sometimes called the witch's egg, the immature stinkhorn is whitish and egg-shaped and up to 6 cm (2 in) in diameter. On the outside is a thick whitish volva, also known as the peridium, covering the olive-coloured gelatinous gleba. It is the latter which contains the spores and which 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), which is hard, but with an airy structure like a sponge. The eggs become fully grown stinkhorns very rapidly, over a day or two.

Uses
At the egg stage, pieces of the inner layer (the receptaculum) can be cut out with a knife and eaten raw. They are crisp and crunchy with an attractive radishy taste. The fungus is enjoyed and eaten in France and parts of Germany, where it may be sold fresh or pickled and used in sausages. Similar species are consumed in China.

It was used as a medieval cure for gout and as a love potion.