426 OBIGIN OP CULTIVATED PLANTS. 



C. Koch^ denied that it was indigenous in Armenia and 

 to the south of the Caucasus, but this has been proved 

 by several travellers. It has since been discovered wild 

 in Japan,^ which renders it probable that the species 

 exists also in the north of China, as Loureiro and Bunge 

 said,^ but without particularizing its wild character. 

 Heldreich* has recently placed it beyond a doubt that 

 the walnut is abundant in a wild state in the mountains 

 of Greece, which agrees with passages in Theophrastus ^ 

 which had been overlooked. Lastly, HeufFel saw it, also 

 wild, in the mountains of Banat." Its modern natural 

 area extends, then, from eaistern temperate Europe to 

 Japan. ' It once existed in Europe further to the west, 

 for leaves of the walnut have been found in the quater- 

 nary tufa in Provence.' Many species of Juglans existed 

 in our hemisphere in the tertiary and quaternary epochs ; 

 there are now ten, at most, distributed throughout North 

 America and temperate Asia. 



The use of the walnut and the planting of the tree 

 may have begun in several of the countries where the 

 species was found, and cultivation extended gradually and 

 slightly its artificial area. The walnut is not one of 

 those trees which sows itself and is easily naturalized. 

 The nature of its fruit is perhaps against this; and, 

 moreover, it needs a climate where the frosts are not 

 severe and the heat moderate. It scarcely passes the 

 northern limit of the vine, and does not extend nearly so 

 far south. 



The Greeks, accustomed to olive oil, neglected the 

 walnut until they received from Persia a better variety, 

 called Icaruon hasiliJcon,^ or Persikon? The Romans 



' 0. Koch, Dendrologie, i. p. 584. 



" Franohet and Savatier, Ermm. Plant. Jap., i. 453. 



* Loareiro, M. Cochin., p. 702 ; Bunge, Unum., p. 62. 



* Heldreich, Verhandl. Boi, Tereins B^-andenb., 1879, p. 147. 



' Theophrastus, Hist. Plant., lib. iii. cap. 3, 6. These passages, and 

 others of ancient writers, are quoted and interpreted by Heldreich better 

 than by Hehn and other scholars. 



* Heneeel, Ahhandl. Zool. Bot. Ges. »» Wien, 1853, p. 194. 

 ' De Saporta, 3Srd 8ess. du Congres Scient, de France. 



' Diosooridea, lib. i. cap. 176. 



» PLny, Hist. Plant., lib. xt. cap. 22. 



