[523] Dr. Hooker has given me this information. See, also, his 'Himalayan Journals,' 1851, vol. ii. p. 49.
[524] 'Travels in Central Africa,' Eng. translat., vol. i. pp. 529 and 390; vol. ii. pp. 29, 265, 270. Livingstone's 'Travels,' p. 551.
[525] As in both North and South America, Mr. Edgeworth ('Journal Proc. Linn. Soc.,' vol. vi. Bot., 1862, p. 181) states that in the deserts of the Punjab poor women sweep up, "by a whisk into straw baskets," the seeds of four genera of grasses, namely, of Agrostis, Panicum, Cenchrus, and Pennisetum, as well as the seeds of four other genera belonging to distinct families.
[526] Prof. O. Heer, 'Die Pflanzen der Pfahlbauten, 1865, aus dem Neujahr. Naturforsc. Gesellschaft,' 1866; and Dr. H. Christ, in Rütimeyer's 'Die Fauna der Pfuhlbauten,' 1861, s. 226.
[527] 'Travels,' p. 535. Du Chaillu, 'Adventures in Equatorial Africa,' 1861, p. 445.
[528] In Tierra del Fuego the spot where wigwams had formerly stood could be distinguished at a great distance by the bright green tint of the native vegetation.
[529] 'American Acad. of Arts and Science,' April 10th, 1860, p. 413. Downing, 'The Fruits of America,' 1845, p. 261.
[530] 'Journals of Expeditions in Australia,' 1841, vol. ii. p. 292.
[531] Darwin's 'Journal of Researches,' 1845, p. 215.
[532] De Candolle has tabulated the facts in the most interesting manner in his 'Géographie Bot.,' p. 986.