Page:Popular Science Monthly Volume 21.djvu/311

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But there are some other plants whose cells exhibit the phenomenon of living, moving protoplasm so much better than nettle-hairs or pumpkin-hairs, that I can not forbear presenting, in concluding the present article, the cells of one more plant. The plant we now select is a very common one in most parts of our country, but on account of its simple and retired habits of life is little known save to the botanist and microscopist. An aquatic plant it is, finding a home in slow-running streams, or shallow ponds whose sandy bottoms reflect the warm rays of the summer sun. Totally immersed in water, however, and so far independent of rains, our plant knows little distinction of spring and summer, and grows on vigorously until the frosts of fall are heavy enough to> seal everything under a covering of ice. If during this long, growing season we collect a sprig of Chara (for such is the name of the plant), we shall find it made up of something like a stem bearing whorls of leaves, or at least of what may pass for leaves. Let us now take one of the newest and smallest of these leaves and place it under our lens. A series of cells, you say. But through the thin wall of any cell appears again a flowing stream. Not the pale, delicate thread of silver we saw feeling its way around the cell-wall of the pumpkin-hair or tomato-hair, but a very river it seems now as it rushes on, wave after wave, up from the depths below across the field of vision and down again, over and over, or round and round, in ceaseless rotation (Fig. 17).



Now the current catches in its course this little particle, now that, hurling each along, now up, now down, now over, now under, without weariness, without hindrance, hour after hour, before us.

And now, as the stream goes on so grandly, think, for a moment, what it is at which we gaze. We call it protoplasm, but it is the current of life, the "physical basis of life"—the common bond which binds in one the whole kingdom of organic things. Think, too, of the antiquity of that stream, its lineage. The brook that "goes on for ever" is as nothing to it, for here the stream has come flowing down through ages which are to us as eternity, ever since life began on earth. The mountains have been hoary with years, and have disappeared beneath the level of the all-producing sea, but this stream is older than they. Continents have grown old, worn out, and been