oH ORIGIN OF CULTIVATED PLANTS. 



the number of varieties suddenly increased in European 

 gardens, and all authors commenced to mention them ; 

 (4) the majority of the species of the genus exist in South 

 America ; (5) seeds apparently belonging to the species 

 have been discovered in Peruvian tombs of an uncertain 

 date, intermixed with many species, all American. 



I do not examine whether Fhaseolus viUgaris existed 

 in both hemispheres previous to cultivation, because 

 examples of this nature are exceedingly rare among 

 non-aquatic phanerogamous plants of tropical countries. 

 Perhaps there is not one in a thousand, and even then 

 human agency may be suspected.^ To open this question 

 in the case of Ph. vulgaris, it should at least be found 

 wild in both old and new worlds, which has not happened. 

 If it had occupied so vast an area, we should see signs 

 of it in individuals really wild in widely separate regions 

 on the same continent, as is the case with the following 

 species, Pit. lunatus. 



Scimetar-podded Kidney Bean, or Sugar Bean. — Pha- 

 seolus lunatus, Linnaeus; Phaseolus lunatus niacrocarpus \ 

 Bentham, Ph. inamwnus, Linn?eus. 



This haricot, as well as that called Lima, is so widely 

 diffused in tropical countries, that it has been described 

 under ditierent names.^ All these forms can be classed 

 in two groups, of which Linnseus made ditierent species. 

 The commonest in our gardens is that which has been 

 called since the beginning of the century the Lima 

 haricot. It may be distinguished by its height, by the 

 size of its pods and beans. It lasts several years in 

 countries which are favourable to it. 



Linnreus believed that his Ph. lunatus came from 

 Bengal and the other from Africa, but he gives no 

 proof. For a century his assertions were repeated. 

 Now, Bentham,^ who is careful about origins, believes the 

 species and its variet}^ to be certainly American ; he only 

 doubts about its presence as a wild plant both in Africa 



' A. de Candolle, Geogr. Bot. Rais., chapter on disjnnctive species. 

 * Ph. hipunctatns, J acqmn; Ph. inamcenus^ Linnaeus j Ph. jpuberulus, 

 KuntVi ; Ph. saccharatits, MacFadyen ; etc., etc. 

 ^ B niham, in Fl. Brat^iL, vol.'xv. p. ISl. 



