8. In the history of cultivated plants, I have noticed no trace of communication between the peoples of the old and new worlds before the discovery of America by Columbus. The Scandinavians, who had pushed their excursions as far as the north of the United States, and the Basques of the Middle Ages, who followed whales perhaps as far as America, do not seem to have transported a single cultivated species. Neither has the Gulf Stream produced any effect. Between America and Asia two transports of useful plants perhaps took place, the one by man (the Batata, or sweet potato) the other by the agency of man or of the sea (the cocoa-nut palm).
[1] Hooker, Flora Tasmaniæ, i. p. cx.
[2] Bretschneider, On the Study and Value of Chinese Botanical Works, p. 7.
[3] De Naidaillac, Les Premiers Hommes et les Temps Préhistoriques, i. pp. 266, 268. The absence of traces of agriculture among these remains is, moreover, corroborated by Heer and Cartailhac, both well versed in the discoveries of archæology.
[4] M. Montelius, from Cartailhac, Revue, 1875, p. 237.
[5] Heer, Die Pflanzen der Pfahlbauten, in 4to, Zurich, 1865. See the article on “Flax.”
[6] Perrin, Étude Préhistorique de la Savoie, in 4to, 1870; Castelfranco, Notizie intorno alla Stazione lacustre di Lagozza; and Sordelli, Sulle piante della torbiera della Lagozza, in the Actes de la Soc. Ital. des Scien. Nat., 1880.
[7] Much, Mittheil d. Anthropol. Ges. in Wien, vol. vi.; Sacken, Sitzber. Akad. Wien., vol. vi. Letter of Heer on these works and analysis of them in Naidaillac, i. p. 247.
[8] Alph. de Candolle, Géographie Botanique Raisonnée, chap. x. p. 1055; chap. xi., xix., xxvii.