The common mushroom (Agaricus campestris) is propagated by spores, the fine black dust seen to be thrown off when a mature specimen is laid on white paper or a white dish; these give rise to what is known as the "spawn" or mycelium, which consists of whitish threads permeating dried dung or similar substances, and which, when planted in a proper medium, runs through the mass, and eventually develops the fructification known as the mushroom.
The railway runs through the centre of the rice-producing area, and feeder roads open up the country as far as the Shan foot-hills.
The Bernam runs through flat swampy country for the greater part of its course, and steam-launches can penetrate to a distance of over 100 m.
The whole tissue system is known as the stelar system (from the way in which in primitive forms it runs through the whole axis of the plant in the form of a column).
In this part of its course the Euphrates runs through an open, treeless and sparsely peopled country, in a valley a few miles wide, which it has eroded in the rocky surface.
