Page:Popular Science Monthly Volume 26.djvu/630

612 pecks of apparently lifeless seed-corn safely housed in the granary. We thus see that in the annual plants the life of the species is, so to speak, carried over from one growing season to another in the ripened seed. The seed is also the form in which plant-life is easily transported from place to place. The seed of some hedgerow weed, as it becomes loosened from its attachment upon the lifeless mother-plant, and is blown for rods or even miles over the surface of the incrusted snow, is a familiar and perhaps striking example that may enforce the meaning to be here conveyed. The young plantlet in the seed, snugly packed within thick coats, is preserved from death, and at the same time is carried far from the place where it was produced. The seed is the offspring of the plant and the childhood of its kind, though so fashioned and protected that it can pass safely through a period of drought or cold when its parent would have succumbed. It is the motile or migratory state of plants, and many are the means of transportation by land, wind, wave, stream, passing herd, and flying bird, that are within its reach.

Biennial plants, like the beet, carrot, etc., spend one season in preparing for the coming days of inactivity and exposure, and close their careers the following year by using up the accumulated store of food in the roots, stems, or leaves, in producing a crop of seeds. These plants have taken one bold step toward that perennial condition of life enjoyed by our shrubs, trees, and many other plants. Even the "giants of the forest" prepare themselves for the trying months of winter; by withdrawing their vital fluid from the delicate leaves, and with apparently lifeless branches bearing buds enwrapped in scales and secured with a natural glue, they brave the winter blasts.

The season of growth is constantly anticipating the days when the streams of vitality must be checked. The gardener may remove his tender plants to a place "under glass," and so change the order of Nature that things get "out of season," but soon the tortured plants must have rest from their labors and an opportunity to reproduce their kind.

With this somewhat lengthy introduction to our subject let us enter a less familiar field of plant-life, and see if we do not find the same rule holding true among the minute and frequently very troublesome plants known as Fungi. Enough is not known of the habits of these low forms of vegetation for us to measure the natural limits of individual existence; in fact, individuality is very obscure, and, being largely creatures of circumstance, multiplication is extremely rapid when conditions are most favorable, and at a standstill when the reverse is true. Some of the simplest forms of this vast group, like the minute bacteria, yeast-cells, etc., pass through many generations in a few hours; while, on the other hand, the larger species of the hard, woody "shelf" fungi, on trunks of trees and old stumps, may represent in a single so-called "individual" the accumulated growths of a score or more of years. The mildews, molds, and fungi of that