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Yes! by a series of resolute efforts, in using a new battery of lenses the finest that at that time had ever been put into the hands of man I was enabled to show in succession that each motile form of Bacterium up to B. lineola accomplished its movements by fibers or flagella; and that in the act of self-division, constantly taking place, a new fiber was drawn out for each half before separation.

At the same moment a motion is set up which pulls the divided pairs asunder, making the interval of sarcode to grow constantly greater between them. During this time the nuclear body has commenced and continued a process of self-division; from this moment the organism grows rapidly rounder, the flagella swiftly diverge.

But when motion is attained we are compelled to abandon the mass and follow one in all its impetuous travels in its little world; and by doing so we are enabled to follow the developed speck into the parent condition and size, and not to leave it until it had, like its predecessors, entered on and completed its wonderful self-division by fission.

We have seen that certain animals, besides the ordinary process of generation, also increase their number naturally and constantly by self-division, so that out of one individual many individuals may arise by a natural breaking up of the whole body into distinct surviving parts.

This process of normal self-division may take place at all periods of life: it may form an early phase of metamorphosis, as in the Hydroid of our common Aurelia, described in the last article; or it may even take place before the young is formed in the egg.

Perhaps the most convincing and beautiful illustration of the truth of this vital and all important proposition is, that the reproductive cells of man in his highest state of development, multiply by fission, or self-division into halves, as did the primal sperm of protoplasm at the very beginning of vegetable and animal life.

We ought therefore to dispense with the useless and gratuitous hypothesis that cells multiply by throwing off minute self-multiplying gemmules, as well as by the well-known method of self-division. If pangenesis occurs, the transmission of acquired characters ought to be a prominent fact.

She points out hopefully that certain marine animals multiply their species by self-division. "The less mind there is manifested in matter, the better. When the unthinking lobster loses his claw, it grows again." If we but believed that matter has no sensation, "then the human limb would be replaced as readily as the lobster's claw."

It reproduces itself, as we have seen, by separation and self-division. The life of the bacteria and germs the yeasty forms of life are familiar to many of us. And yet there are forms of life still below these. The line between living forms and non-living forms is being set back further and further by science.

The cell can secrete and excrete substance, and, in brief, presents nearly all the phenomena of a human being. Cells are produced only from cells by a process of self-division, consisting of a cleavage of the whole cell into parts, each of which becomes a separate and independent organism. Cells rapidly increase in size up to a certain definite point which they maintain during adult life.