Page:Once a Week Volume 7.djvu/271

. 30, 1862.] 

to enlargement of the root, would produce a certain number of specimens with still larger roots; and, by pursuing this system of selection through several generations, a race of plants producing, in a favourable soil, roots of truly enormous dimensions would, with certainty, be produced. It was, by such a process, that our well-known esculent, the common carrot, was produced. An experimental botanist, in the south of France, tested the truth of this theory a few years since. The original transition, no doubt, occurred long ages ago,—in times when essays and books were not very commonly written upon such subjects, so that there is no record of the occurrence. The esculent carrot was, however, in all probability, well known to ancient nations, along with many other similar vegetable monstrosities which have fallen out of culture and been forgotten during the temporary supremacy of the barbarians who overrun the Roman empire. However, this may be, the cultivated carrot appears to have been introduced into England about the reign of Henry the Eighth, being imported from Flanders, the source of many other of our most valuable garden vegetables.

The experimental botanist above alluded to, in order to carry out his experiments concerning the origin of the garden carrot from the weed Daucus carota, gathered seed of the wild plant, and, treating it as above described, found that it required only seven seasons to transform the hard woody root into a tolerably good carrot. This positive result at once silenced the outcry of those who did not believe in such transitions, and proclaimed the garden carrot a separate and distinct species. Scepticism, in such a case, is very excusable, for the degree to which herbaceous plants may be diverted from their natural forms of growth by watchful culture, would scarcely be believed, unless every step in the gradual departure from the original type could be proved. The steps by which plants, now in the most abundant cultivation in their present forms, have gradually diverged from their wild types has recently been proved to demonstration by botanical physiologists, in other cases than that of the carrot; and may be proved over and over again by any student willing to devote a few days—once or twice a-year—for a sufficient number of seasons, to put the theory to the test of actual trial; that is to say, if the right plant be selected for the experiment.

These changes, however, are not to be made in any ordinary plant, either by stimulating manures or any other kind of artificial culture; but can only be produced by observing a tendency to aberrations of growth in certain individuals of a genus, and carefully selecting the seed from those plants most inclined to exhibit such unusual or monstrous kind of growth. These selected seeds will produce plants, most of which will revert to the original wild type, but, in nearly all cases, a few will be developed into plants having a more or less tendency to aberration of the same kind as that of the immediate parent. A few, possibly, may exhibit the same kind of monstrosity in a more exaggerated form, and the seed produced by these will, in all probability, produce a much larger proportion of plants exhibiting the desirable monstrosity.

The turnip, the radish, and many other plants whose radical monstrosities have been perpetuated and increased by culture, might be described, along with the precise character of their irregular growth; but my space does not permit of my saying more on root monstrosities.