The most serious disease with which the bee-keeper has to contend is that commonly known as " bee-pest " or " foul brood," so called because of the young brood dying and rotting in the cells.
The spores, which are set free by the rotting of the sporangial wall, germinate much as in the case of Selaginella, though the similarity may be a case of independent resemblance.
In some variants of the story this shell is said to grow as a kind of mushroom on rotting timber in the sea, and is obviously one of the barnacles of the genus Lepas.
It is a colourless, extremely poisonous gas, possessing a characteristic offensive smell, resembling that of rotting fish.
They are eminently dry-country plants (xerophytes); the narrow leaves are protected from loss of water by a thick cuticle, and have a well-developed sheath which embraces the stem and forms, with the sheaths of the other leaves of the rosette, a basin in which water collects, with fragments of rotting leaves and the like.