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SEX IN EDUCATION.
simplest. It is merely the replacing of one microscopic cell by another; and yet upon this simple process hang the issues of life and death, of thought and power.
Carpenter, in his physiology, reports the discovery, which we owe to German investigation, “ that the whole structure originates in a single cell; that this cell gives birth to others, analogous to itself, and these again to many future generations ; and that all the varied tissues of the animal body are developed from cells.” * A more recent writer adds, “In the higher animals and plants, we are presented with structures which may be regarded as essentially aggregates of cells; and there is now a physiological division of labor, some of the cells being concerned with the nutriment of the organism, whilst others are set apart, and dedicated to the function of reproduction. Every cell in such an aggregate leads a life, which, in a certain limited sense, may be said to be independent; and each discharges its own function in the
* Carpenter’s Human Physiol »gy, p. 455.