Chai\ IX. 



PRELIMINARY REMARKS. 



329 



their having practised artificial irrigation and made tunnels 

 through hard rocks without the use of iron or gunpowder, 

 and who, as we shall see in a future chapter, fully recognised, 

 as far as animals were concerned, and therefore probably in 

 the case of plants, the important principle of selection. We 

 owe some plants to Brazil ; and the early voyagers, namely, 

 Vespucius and Cabral, describe the country as thickly peopled 

 and cultivated. In North America 16 the natives cultivated 

 maize, pumpkins, gourds, beans, and peas, " all different from 

 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 



Cereal ia. — I will now enter on details. The cereals cultivated in 

 Europe consist of four genera — wheat, rye, barley, and oats. Of 

 wheat the best modern authorities 18 make four or five, or even 

 seven distinct species; of rye, one; of barley, three; and of oats, 

 two, three, or four species. So that altogether our cereals are 

 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 are not universally agreed on the 

 aboriginal parent-form of any one cereal plant. For instance, a 



16 For Canada, see J. Cartier's 

 Voyage in 1534; for Florida, see 

 Narvaez and Ferdinand de Soto's 

 Voyages. As I have consulted these 

 and other old Voyages in more than 

 one general collection of Voyages, I 

 do not give precise references to the 

 pagus. See also, for several references, 

 Asa Gray, in the ' American Journal 

 of Science,' vol. xxiv. Nov. 1857, p. 

 441. For the traditions of the natives 

 of New Zealand, see Crawfurd's 

 ' Grammar and Diet, of the Malay 

 Language,' 1852, p. eclx. 



17 See, for example, Mr. Hewett C. 

 Watson's remarks on our wild plums 

 and cherries and crabs : ' Cybele 

 Britannica,' vol. i. pp. 330, 334, &c. 

 Van Mons (in his 'Arbres Fruitiers,' 

 1835, torn. i. p. 444) declares that he 

 has found the types of all our culti- 

 vated varieties in wild seedlings, but 

 then he looks on these seedlings as so 

 many aboriginal stocks. 



18 "See A. De Candolle, < Geogroph. 

 Bot.,' 1855, p. 928 et seq. Godror, 

 ' De l'Espece,' 1859, torn. ii. p. 70 ; and 

 Metzger, ' Die Getreidearten,' &c, 1841. 



