76 OEIGIN OF CULTIVATED PLANTS. 



mentioned also in India ^ and ^n Australia,^ but its wild 

 condition is not affirmed — a fact always difficult to 

 establish in the case of a species cultivated on the banks 

 of streams, and which is propagated by bulbs. More- 

 over, it is sometimes confounded with the Colocasia 

 indAca of Kunth, which grows in the same manner, and 

 is found here and there in cultivated ground ; and this 

 species grows wild, or is naturalized in the ditches and 

 streams of Southern Asia, although its history is not yet 

 well known. 



Eonjak — Amorphophallus Konjak, Koch ; Amor- 

 phophallus Rivieri, du Rieu, var. Konjak, Engler.* 



The konjak is a tuberous plant of the family 

 Aracese, extensively cultivated by the Japanese, a culture 

 of which Vidal has given full details in the Bulletin de 

 la Societe d'Acclimatation of July, 1877. It is consi- 

 dered by Engler as a variety of ATnorphophallus Eivim, 

 of Cochin-China, of which horticultural periodieala 

 have given several illustrations in the last few years.* 

 It can be cultivated in the south of Europe, like the 

 dahlia, as a curiosity ; but to estimate the value of the 

 bulbs as food, they should be prepared with lime-water, 

 in Japanese fashion, so as to ascertain the amount of 

 fecula which a given area will produce. 



Dr. Vidal gives no proof that the Japanese plant is 

 wild in that country. He supposes it to be so from the 

 meaning of the common name, which is, he says, konni- 

 yakou, or yamagonniyakou, yama meaning " mountain." 

 Franchet and Sayatier ^ have only seen the plant in 

 gardens. The Cochin-China variety, believed to belong 

 to the same species, grows in gardens, and there is no 

 proof of its being wild in the country. 



Yams — Dioscorea sativa, D. batatas, D. japonica, 

 and D. alata. 



The yams, monocotyledonous plants, belonging to 



' Engler, in D. 0. Monog. Phaner. 

 ' Bentham, Mora Austr., viii. p. 155. 

 " Engler, in D. C. Monogr. Phaner., vol. ii. p. 313. 

 * Gardener's Chronicle, 1873, p. 610; Flore des Senses et Jardins, 

 t. 1958, 1959 ; Hooker, Bot. Mag., t. 6195. 



" Pranohet and Savatier, Enum, PI, Japonim, ii. p. 7. 



