Die Schwellenregeln in der Sinnesphysiologie und das by Y. Reenpää

By Y. Reenpää

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Extra info for Die Schwellenregeln in der Sinnesphysiologie und das psychophysische Problem

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21 THE MOLDS AND MAN Fungi have no chlorophyll, and therefore can not use the energy of the sun directly, as the green plants do. They must live either as saprophytes, on dead material, or as parasites, on living material. Many of them can live either as parasites or as saprophytes, as the occasion offers. The growth of fungi is affected by temperature, water, oxygen, food, toxic materials, and some other factors not discussed above. Among the common fungi are those that endure less water, a lower temperature, a higher temperature, or a higher concentration of toxic materials than almost any other organisms on earth.

Stalks grow out from the walls of this cavity, a spore is formed on the tip of each stalk, released as soon as it is mature, another is formed, and so on, until the cavity is filled with millions of spores, all of them em- *7 THE MOLDS AND MAN bedded in a sticky matrix. This matrix has the ability to absorb water and swell rapidly. When moistened by rain, it swells; spores and matrix are forced out of the fruit body in the form of a twisted red or yellow tendril. A single one of these small, pimple-like fruit bodies, technically known as a pycnidium, may exude from half a billion to a billion spores.

The odor, so unpleasant to us, is attractive to carrion flies, who often cluster in hordes around a freshly risen stinkhorn. They mistake its odor for the odor of carrion. They mess around in the evil liquid, pick up a heavy load of spores, and presumably carry them to those places where stinkhorn spores can grow. So far as is known, the flies get no benefit from this. But it is somewhat remarkable that an organism at the bottom of the scale of evolution, as fungi supposedly are, should have found out that certain kinds of flies relish the odor of carrion, have then gone ahead and produced it, together with a sticky material in which its spores are embedded, and finally have developed a means of getting the ill-smelling mass up into the air where the flies can get at it.

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