Page:An introduction to physiological and systematical botany (1st edition).djvu/131

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OF THE COTYLEDONS.
101

seeds in the earth, there is also an evolution of a considerable portion of heat. This indeed might have been expected, as it usually happens when oxygen gas is absorbed. So far seems to be the work of chemistry alone; at least we have no right to conclude that any other agent interferes; since hay, when it happens to imbibe moisture, exhibits nearly the same processes."

I conceive the evolution of this heat may powerfully further the progress of vegetation by stimulating the vital principle of the embryo, till its leaves unfold and assume their functions. It is necessary to observe, that the above process equally takes place, whether the farinaceous particles be lodged in the bulk of the cotyledons themselves, or compose a separate body called by authors the albumen, as in grasses and corn.