From these data and reflections it is probable that at the end of the nineteenth century men will cultivate on a large scale and for use about three hundred species. This is a small proportion of the one hundred and twenty or one hundred and forty thousand in the vegetable kingdom; but in the animal world the proportion of creatures subject to the will of man is far smaller. There are not perhaps more than two hundred species of domestic animals—that is, reared for our use,—and the animal kingdom reckons millions of species. In the great class of molluscs the oyster alone is cultivated, and in that of the Articulata, which counts ten times more species than the vegetable kingdom, we can only name the bee and two or three silk-producing insects. Doubtless the number of species of animals and vegetables which may be reared or cultivated for pleasure or curiosity is very large: witness menageries and zoological and botanical gardens, but I am only speaking here of useful plants and animals, in general and customary employment.
Article III.—Cultivated Plants known or not known in a Wild State.
Science has succeeded in discovering the geographical origin of nearly all cultivated species; but there is less progress in the knowledge of species in a natural state—that is wild, far from cultivation and dwellings. There are species which have not been discovered in this condition, and others whose specific identity and truly wild condition are doubtful.
In the following enumeration I have classed the species according to the degree of certainty as to the wild character, and the nature of the doubts where such exist.[2182]
1. Spontaneous species, that is wild, seen by several botanists far from dwellings and cultivation, with every appearance of indigenous plants, and under a form identical with one of the cultivated varieties. These are the species which are not enumerated below; they are 169 in number.
Among these 169 species, 31 belong to the categories A and D, of very ancient cultivation, 56 have been in cultivation less than two thousand years, C, and the others are of modern or unknown date.
2. Seen and gathered in the same conditions, but by a single botanist in a single locality. Three species.
Cucurbita maxima, Faba vulgaris, Nicotiana Tabacum.
3. Seen and mentioned but not gathered in the same conditions by one or two authors and botanists, more or less ancient, who may have been mistaken. Two species.
Carthamus tinctorius, Triticum vulgare.