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Show 320 CEREAL PLANTS. CIIAP. IX. Finally, every one must judge for himself whether it is more probable that the several forms of wheat, barley,. rye, and oats arc descended from between ten and :fifteen species, most of which arc now oW1er unknown or extinct, or whether they arc uescended from between four and eight species, which may have either closely resembled our present cultivated forms, or have been so widely diiTorent as to escape identification. In this latter case, we must conclude that man cultivated tho cereals at an enormously remote period, and that he formerly practised some degree of selection, which in itself is not improbable. V\T o may, perhaps, further believe that, when wheat was first cultivated, the ears and grains increased quickly in size, in the same manner as the roots of the wild carrot and parsnip are known to increase quickly in bulk under cultivation. Maize: Zea Mays.-Botanists are nearly unanimous that all the cultivated kinds belong to the same species. It is undoubtedly 47 of American origin, and was grown by ~ tho aborigines throughout tho continent from Now England to Chili. Its cultivation must havo beon extremely ancient, for Tschudi 43 describes two kinds, now extinct or not known in Peru, which wcro taken from tombs apparently prior to tho dynasty of tho Incas. But there is even stronger evidence of antiquity, for I found on tho coast of Peru 49 heads of maize, together with eighteen species of recent sea-shell, embedded in a beach which had been upraised at least 85 foot above the level of the sea. In accordance with this ancient cultivation, numerous American varieties havo arisen. The aboriginal form has not as yet been discovered in the wild state. A peculiar kind/0 in which tho grains, instead of being naked, aro con~ealed by husks as much as eleven lines in length, has been stated on insufficient evidence to grow wild in Brazil. It is almost certain that the aboriginal form would have had its grains thus protected; 51 but tho seeds of the Brazilian variety produce, as I hoar from Professor Asa Gray, and as is stated in two published accounts, either common or husked maize ; and it is not ere- '17 See Alph. De Oandollo's long discussion in bis 'Gcograph. Bot.,' p. 942. With respect to Now England, see Silliman's 'AmoricauJournal,'vol.xliv. p. 99. 43 'Travels in Peru,' Eng. transbt., p.177. 49 'Gcolog. Obscrv. on S. America,' 1846, p. 49. 50 This maize is figured il'l Bonafous' magnificent work, 'IIist. Nat. du Mais,' 1836, Pl. v. bis, and in the 'Journal of Hort. Soc.,' vol. i., 1846, p. 115, whore an account is given of the result of sowing tho seed. A young Guamny Indian, on seeing this kind of mA,izo, told Auguste St. Hilaire (see Do Candollc, 'Gcogmph. Bot.,' p. 951) that it grew wild in tho humid forests of his native lnnd. Mr. Tcschcmncher, in 'Proc. Boston Soc. Nnt. Hist.,' Oct. 19th, 1842, gives an account of sowing the seed. 51 1\foquin-Tandon, 'Elements do Teratologic,' 1841, p. 126. CHAP. IX. MAIZE. 321 diblo that a wild spocios, when frrst cultivated, should vary so quickly and in so great a degree. Maize has varied in an extraordinary and conspicuous manner. Metzger, 52 who paid particular attention to the cultivation of this plant, makes twelve races (untcr-art) with numerous sub-varieties· of tho latter some aro tolerably constant, others quito inconstant. 'fhe different races vary in hei?ht from 15-18 feet to only 16-18 inches, as in a dwarf variety doscnbcd by Bonafous. The wholo car is variable in shape, being long and narrow, or short and thick, or branched. The car · in one variety is moro than four times as long as in a dwarf kind. Tho seeds arc arranged in tho car in from six to oven twenty rows, or aro placed irregularly. Tho seeds aro coloured-white, pale-yellow, orange, red, violet, or elegantly streaked with black; 53 and in tho same car there are sometimes seeds of two colours. In a small collection I found that a single grain of one variety nearly equalled in weight seven grains of another variety. The shape of tho seed varies greatly, being very flat, o~ nearly globular, or oval; broader than long, or longer than broad; Without any point, or produced into a sharp tooth, and this tooth is sometimes rccurvcd. One variety (tho rugosa of Bonafous) has its seeds cur~ously Wl'inJdcd, giving to tho whole car a singular appearance. Another vanoty (tho cymosa of Bon.) carries its cars so crowded together that it is cal~ cd ma'is a boul)ttet. The seeds of some varieties contain much glucose mstead of starch. Male flowers sometimes appear amongst the female flowers, and Mr. J. Scott has lately observed the rarer case of female flowers on a true malo panicle, and likewise hermaphrodite flowers.M Azara describes 55 a variety in Paraguay tho grains of which aro very tender, and ho states that several varieties arc fitted fOl' being cooked in v~r~ous ways. Tho varieties also differ greatly in precocity, and have different powers of resisting dryness and tho action of violent wind.&G Some of the foregoing differences would certainly be considered of specific value with plants in a state of nature. Le Oomtc Rc states that the grains of all the varieties which he cultivated ultimately assumed a yellow colour. But Bonafous 57 found that mo~t of those. which he sowed for ten consecutive years kept true to thcrr proper tmts ; and ho adds that in the valleys of tho Pyrenees and on tho plains of Piedmont a white maize has been cultivated for more than a centmy, and has undergone no change. The tall kinds grown in southern latitudes, and therefore exposed to great heat, require from six to seven months to ripen their seed · whereas the dwarf kinds, grown in northem and colder climates, require ~nly from "2 'Dio Getreidcarten,' 1841, s. 208. I have modified a fow of Metzger's statements iu accordance with those made by BonoJous in his great work, 'IIist. Nat. du Mai:s,' 1836. 53 Godron, 'Do l'Espccc,' tom. ii. p. 80; Al. De Candollo, idom, p. 951. VOL. l. 54 ' Transact. Bot. Soc. of Edinburgh,' vol. viii. p. GO. 55 •Voyages dans !'Amerique Meridionale,' tom. i. p. 147. "6 Bonal'ous' 'Hist. Nut. du Ma'is,' p. 31. 57 Idem, p. Rl. y |