nut, the plum, the apricot, the peach, the cherry, etc. In extending their domination from one extremity of the ancient world to the other, the Arabs still found something to glean, and the Crusaders took numerous loans from them. Europe then acquired rice, sugar cane, and the orange. Finally, since the great expeditions of the Renaissance, the flora of the entire world has been put under contribution. The Romans caused trees loaded with fruit to figure in their triumphs, in testimony, Pliny says, of a victory which had been gained over Nature not less than over men. Thus, wherever civilization established itself it sought, in order to make itself welcome and its presence a blessing, to lavish upon the new lands the gains which it had accumulated in its former cultivations. Like the gods of other days, when they descended among men, it appeared with its hands full of precious gifts. This propagation of useful plants is of itself so great a benefit that it compensates, and more, for all the evil that civilization has been accused of spreading.

During the course of the subjection of the vegetable world to our use, the conquest has followed an order upon which the documents of the past do not always cast a sufficient light, but of which it i^ possible to restore the stages by means of a logical induction, while bearing in mind the urgency of the needs, the difficulties of cultivation, and the complexity of the uses. The first plants which man interested himself in propagating were those which would assure his subsistence, for the demands of hunger are the most imperious. Then came economical and medicinal plants. The industrial species usually belong to a later stage. Ornamental and fanciful species were a late gain and the luxury of an already rich civilization.