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Show 012 CEREAL PLANTS. CHAP. IX. and cultivated. In North America 16 the natives cultivated maize, pum1 kins, gourds, beans, and peas, "all different frnm ours," and tobacco; and we are hardly justified in assuming that none of our present plants are descended from these North American forms. Had North America been civilized for as long a period, and as thickly peopled, as Asia or Europe, it is probable that the native vines, walnuts, mulberries, crabs, and plums, would. have given rise, after a long course of cultivation, to a multitude of varieties, some extremely different from their parent-· stocks; and escaped seedlings would have caused in the New,. as in the Old World, much perplexity with respect to their specific distinctness and parentage.17 Oerealia.-l will now ontor on details. The cereals cultivated in Em·opo consist of foUl' genera-wheat, rye, barley, and oats. Of wheat the best modern authorities 18 make four or five, or oven seven distinct species; of rye, one? of barley, throe; and of oats, two, three, or four species. So that altogether our cereals arc ranked by different authors under from ten to fifteen distinct species. These have given rise to a multitude of varieties. It is a remarkable fact that botanists arc not universally agreed on tho aboriginal parent-form of any one cereal plant. For instance, a high authority m·ites in 1855,19 "Wo ourselves have no hesitation in stating our conviction, as tho result of all tho most reliable evidence, that none of those Corcalia exist, or have existed, truly wild in their present state, but that all are cultivated varieties of species now growing in groat abundance in S. Europe or W. Asia." On tho other hand, Alph. Do Candollo 20 has adduced abundant evidence that common wheat (1hticum vulgare) has been found wild in various parts of Asia, where it; is not likely to have escaped from cultivation; and thoro is 16 For Canada, see J. Cartier's Voyage in 1534; for Flori<ln, see Narvaez and Ferdinand do Soto'l:! Voyages. As I have consulted these and other old Voyages in moro than one general collection of Voyages, I do not give precise references to tho pages. See also, for several references, Asa Gmy, in tho 'American Journal of Science,' vol. xxiv., Nov. 1857, p. 441. For tho traditions of tho natives of Now Zealand, see Orawfurd's 'Grammar and Diet. of the Malay Langunge,' 1852, p. cclx. 17 See, for cxampl , M. Hewett 0. Watson's remarks on our wild plums o.nd cherries and crabs. • Oybelo Britaunica,' vol. i. pp. 330, 334, &c. Van Mons (in Jds 'Arbrcs Fruiticrs,' 1835, tom. i. p. 414) declares that he bas found the types of all our cultivated vari eties in wild seedlings, but thou ho looks on these seedlings us so many aboriginal stocks. 18 See A. De Oandollo, ' Geograplt. Dot.,' 185!1, p. 928 et seq. Godron, 'De l'Espcoc,' 1859, tom. ii. p. 70; and Metzger, 'Dio Gctreidcartcn,' &c., 1841. lO Mr. Bentham, in his review, entitled 'Hist. Notes on cultivated Plants,' by Dr. A. Targioni·Tozzctti, in' Journal of Hort. Soc.,' vol. ix. (1855), p. 133. 2o 'Geograph. Bot.,' p. 928. 'fhe whole subject is discussed with admirable fullucss and knowledge. CHAP, IX. WIIEAT. 313 force in M. Godron's remark, that, supposing those plants to bo escaped seodlings,21 if they have propagated themselves in ~ wild state for sovor~l generations, their continued rosomblanco to cultivated wheat renders 1t probable that tho latter has reta.inod its aboriginal c~aractor. M. ?e Candollo insists strongly on tho frequent occurrence rn tho Austnan dominions of rye and of one kind of oats in an apparently wild conclition. With tho exception of those two cases, which however arc rather doubtful, and with tho exception of two forms of wheat and one of barley, which ho believes to have boon found truly wild, M. Do Candollo does not seem fully satisfied with tho other reported discoveries of tho parent-forms of our other cereals. With respect to oats, according to Mr. Buckman,22 tho wild English Avenct jatua can be converted by a few years of careful cultivation and selection into forms almost identical with two very distinct cultivated races. The whole subject of tho origin and specific distinctness of tho various cereal plants is a most difficult one; but wo shall perhaps be able to judge a little better afte1· considering the amount of variation which wheat has undergone. Metzger describes seven species of wheat, Godron ~·ofers to five, and De Candollo to only four. It is not improbable that, besides tho kinds known in Europe, other strongly characterised forms exist in the more distant parts of tho world; for Loiscl9Ul'-Doslongchamps 23 speaks of throe now species or varieties, sent to Europe in Ul22 fi·om Chinese Mongolia, which ho considers as being thoro indigenous. Moorcroft 24 also speaks of Hasora wheat in Ladakh as very peculiar. If those botanists are right who believe that at least seven species of wheat originally existed, then the amount of variation in any important character which wheat has undergone under cultivation has boon slight; but if only four or a lesser number of species originally existed, then it is evident that varieties so strongly marked have arisen, that they have been considered by capable judges as specifically distinct. But tho impossibility of deciding which forms ought to bo ranked as species and which as varieties, makes it useless to specify in detail tho differences between tho various kinds of wheat. Speaking generally, tho organs of vegetation differ little; 25 but some kinds grow close and upright, whilst others spread and t1~ail along tho ground. Tho straw differs in being more or loss hollow, and in quality. The ears 26 21 Godron, 'De l'Especc,' tom. ii. p. 72. A few years ago tho excellent, though misinterpreted, observations of M. Fabre leu many persons to believe that wheat was a modified descendant of 1Egilops; but M. Godron (tom. i. p. 1G5) has shown by careful cxpcrimeuts that tho first step in tho series, viz. JEgilops triticoides, is a hybrid between wheat and lE. ovata. Tho frequency with which these hybrids spontaneously arise, and the gradual manner iu which the .EE. triticoides becomes con-vcrtcd into true wheat, alone leave any doubt ou tho subject. 2'2 Report to British Association for 1857, p. 207. 23 'Considerations sur les Oerealcs, 1842-43, p. 29. 24 ''l'ravcls in the Himalayan Provinces,' &c., 1841, vol. i. p. 224. 25 Col. J. Lc Oouteur on tho 'Varieties of Wheat,' pp. 23, 79. 26 Loiseleur-Deslongchamps,' Oonsicl. sur les Oerealcs,' p. 11. |