Hydra- Agaric (Wikipedia)
An agaric (/ˈæɡərɪk, əˈɡærɪk/) is a type of fungus fruiting body characterized by the presence of a pileus (cap) that is clearly differentiated from the stipe (stalk), with lamellae (gills) on the underside of the pileus. In the UK, agarics are called “mushrooms” or “toadstools”. In North America they are typically called “gilled mushrooms”. “Agaric” can also refer to a basidiomycete species characterized by an agaric-type fruiting body.