A statement of the difference between European and American grapes shows why American viticulturists have been so eager to grow either pure-breds from the foreign grape or hybrids with it. [Illustration: FIG. 49. E. S. Rogers.] European grapes have a higher sugar-and-solid content than the American species; they, therefore, make better wines and keep much longer after harvesting and can be made into raisins. Also, they have a greater variety of flavors, which are more delicate, yet richer, with a pleasanter aroma, seldom so acid, and are always lacking the disagreeable, rancid odor and taste, the "foxiness," of many American varieties. There is, however, an unpleasant astringency in some of the foreign grapes, and many varieties are without character of flavor. American table-grapes, on the other hand, are more refreshing, the unfermented juice makes a pleasanter drink, and lacking sweetness and richness, they do not cloy the appetite so quickly. The bunches and berries of the European grapes are larger, more attractive and are borne in greater quantities. The pulp, seeds and skins are somewhat objectionable in all of the native species and scarcely so at all in the Old World sorts. The berries of the native grapes shell from the stem so quickly that the bunches do not ship well. The vines of the Old World grapes are more compact in habit and require less pruning and training than do those of the native grapes; and, as a species, probably through long cultivation, they are adapted to more kinds of soil, to greater differences in environment and are more easily propagated than the American species. Because of these points of superiority in the Old World grape, since Valk, Allen and Rogers showed the way, American grape-breeders have sought to unite by hybridization the good characters of the Old World grape with those of the American. Nearly half of the 2000 grapes cultivated in eastern America have more or less European blood in them. Yet, despite the efforts of the breeders, few of these hybrids have commercial value. Whether because they are naturally better fixed, or long cultivation has more firmly established them, the vine characters of _Vitis vinifera_ more often appear in varieties arising as primary hybrids between that and the native species, and the weaknesses of the foreign grape, which prevent their cultivation in America, crop out. Hybrids in which the vinifera blood is more attenuated, as secondary or tertiary crosses, give better results.