108 SELECT PLANTS FOR INDUSTRIAL CULTURE 



requires soaking before boiling. It has proved hardy in the 

 Southern States of North America. Starch is very profitably 

 obtainable from the tubers. 



Dioscorea spicata, Roth. 



India. Root used like those of other species. 



Dioscorea tomentosa, Koenig. 



Ooyala Yam. India. The nomenclature of some of the Asiatic 

 species requires further revision. 



Dioscorea trifida, Linn6 fil. 



Central America. One of the Yams there cultivated. Various 

 other tuberous Dioscorese occur in tropical countries, but their 

 respective degrees of hardiness, taste, and yield are not recorded or 

 ascertained. The length of the warm season in many extra- 

 tropical countries is probably sufficient for ripening all these Yams. 



Diospyros Ebenum, Koenig.* 



Ceylon, where it furnishes the best kind of Ebony wood. It is 

 not uncommon up to 5,000 feet in that island, according to Dr. 

 Thwaites ; hence I would recommend this large and valuable tree 

 for test plantations in warm extra-tropical lowland forest regions, 

 where also D. qusesita and D. oppositifolia (Thwaites), the best 

 Calamander Trees and D. melanoxylon, should be tried. Many 

 other species of Diospyros could probably be introduced from the 

 mountains of various tropical regions, either for the sake of their 

 ebony-like wood or their fruit. Black Ebony wood sinks in water. 

 The price in England ranges from 8 to <10 per ton, from 700 to 

 1,000 tons being imported into Britain annually for pianoforte 

 keys, the string-holders of musical instruments, the fingerboard and 

 tail-piece of violins, sharp note-pieces of pianos and harmoniums 

 and cabinet organs, and other select purposes. The following 

 species yield Ebony wood, according to Hiern, some of which may 

 prove hardy : Indian D. Ebenum, Koen. ; D. melanoxylon, Roxb. ; 

 D. silvatica, Roxb. ; D. Gardner!, Thw. ; D. hirsuta, L. fil. ; D. 

 discolor, Willd. ; D. Embryopteris, Thw. ; D. Ebenaster, Retz. ; D. 

 montana, Roxb. ; D. insignis, Pers. j D. Tupru, Hamilt. ; D. 

 truncata, Zoll. j D. ramiflora, Wall. African D. Dendo, Welw. ; 

 D. mespiliformis. Hochst. Mauritius D. tesselaria, Poiret. 

 Madagascar D. haplostylis, Boivin ; D. microrhombus, Hiern. 



Diospyros Kaki, Linne fil. 



The Date Plum of China and Japan. A slow-growing not very 

 productive tree, here recorded for completeness. The fruit is 

 yellow or pink, or dark purple, variable in size, but seldom larger 



