CHAPTER n. 



METHODS FOR DISCOVERING OR PROVING THE ORIGIN OP 



SPECIES. 



1. General reflections. As most cultivated plants have 

 been under culture from an early period, and the ma,nner 

 f>f their introduction into cultivation is often little known, 

 different means are necessary in order to ascertain their 

 . .rigin. For each species we need a research similar to 

 those made by historians and archaeologists — a varied 

 research, in which sometimes one process is employed, 

 sometimes another ; and these are afterwards combined 

 and estimated according to their relative value. The 

 naturalist is here no longer in his ordinary domain of 

 observation and description; he must support himself 

 by historical proof, which is never demanded in the 

 laboratory; and botanical facts are required, not with 

 respect to the physiology of plants — a favourite study of 

 the present day — but with regard to the distinction of 

 species and their geographical distribution. 



I shall, therefore, have to make use of methods of 

 Avhich some are foreign to naturalists, others to persons 

 versed in historical learning. I shall say a few words 

 of each, to explain how they should be employed and 

 what is their value. 



2. Botany. One of the most direct means of dis- 

 covering the geographical origin of a cultivated species, 

 is to seek in what country it grows spontaneously, and 

 without the help of man. The question appears at the 

 first glance to be a simple one. It seems, indeed, thai 



