4) ORIGIN OF CULTIVATED PLANTS. 



reason of the distance, and those of the intertropical 

 zone were exchidcd by pjreat droufrlitor by the absence of 

 a hi^h teinporature. At the same time, tlic indigenous 

 species are very pooi'. It is not merely the ^vant of 

 intelligence or of security "which lias prevented the in- 

 habitants from cultivating them. The nature of the 

 indigenous Hora has so much to do with it, that the 

 Europeans, established in these countries for a hundred 

 years, have only cultivated a single species, the Tctva- 

 (jonla, an insignificant green vegetable. I am aware 

 that Sir Joseph Hooker^ has CTnunerated more than a 

 liundred Australian si)ecies which may be used in some 

 "way; but as a matter of lact they were not cultivated 

 by the natives, and, in spite of the improved methoils of 

 the English colonists, no one does cultivate them. This 

 clearly tlemonstiates the ])rinciple of which I spoke just 

 now, that the choice of species is more important tlian 

 the selection of varieties, and that there must be valuable 

 qualities in a wild plant in order to lead to its cultivation. 

 In s])ite of the obscurity of the beginnings of culti- 

 vation in each region, it is certain that they occurred at 

 very different periods. One of the most ancient examples 

 of cultivated i>lants is in a drawinir reiiresentincf iiL's, 

 found in Egypt in the pyramid of Ciizeh. The epoch of 

 the construction of this monument is unceitain. Authors 

 have assigned a date varying between fifteen hundred and 

 four thousaml two hundred years before the Christian era. 

 Sujiposing it to l)e two thousand years, its actual age 

 would be four thousand years. !Now, the construction 

 of the pyramids could oidy have been the work of a 

 numerous, oi'ganized people, possessing a certain degree of 

 civilization, and conseipiently an established agriculture, 

 dating from some centuries back at least. In China, two 

 thousand seven hundred years before Christ, the Emperor 

 Chenming instituted the ceremony at which every year 

 five species of useful ])lants ai'e sown rice, sweet potato, 

 wheat, and two kinds of millet.'^ These plants must 



ITookor, Flora Taamaniiv, \. p. ex. 

 BiolBclinoidLT, On the Sduhj and Value of Chinese Butanical Works, 

 p. 7. 



