YIELDS OF THE LESSER YAM AND OF SOME 



AFRICAN YAMS 



In the Gardens' Bulletin, Vol. 1, pp. 396-399 (191?) an illus- 

 trated account of the Lesser Yam — Dioscorea esculenta, (Lour.) 

 Burk., was given. The purpose of that account was to indicate 

 its root-characters and to show how the several races, then in 

 culti\ation, differed from each other. Those races came from 

 India, French Indo-China and the Philippine islands. Since 1917 

 three races from Pa]:)ua have heen introduced into the Botanic 

 Grardens, Singapore, by the kindness of His Excellenc.v Judge J. 

 H. P. Murray, Lieut.-Governor of Papua : they liear names ascribed 

 to the Hanuabada language, and are apparently from the country 

 to the west of Port Moresby. These three races are figured on the 

 plate with this issue. One of them is quite unlike any of the races 

 experimentally grown earlier ; the other two are like the Philippine 

 race " Buga '"' in general characters. All three produce male flow- 

 ers, and are wild in Papua. This production of male flowers in 

 wild races is one of the most curious things ahont Dioscorea 

 esculenta, which otherwise produces no flowers at all. To under- 

 stand how the female flowers alone should bave Ijeeu lost is im- 

 possible with our present knowledge. 



The wild and cultivated races which have been grown in the 

 Botanic Gardens are : — 



Wild. Cultivated. 



"Buga" of the Mountain Pro- "China alu '" of Assam. 



vince of Luzon, also called " Goradu " of the west Deccan 

 "Carot'^ in Pangasinan, Luzon. of India. 



" Pora alu " of Chittagong. 

 "Tailukava" of Papua. "Tugui" of Luzon. 



"Invod" of Palawan. 

 " Deba " of Papua. " Khoai tu bua " of Saigon. 



" Khoai cliach " of Saigon. 

 "Memu" of Papua. " Tu-cu " of Saigon. 



" Moa alu " of Assam. 



All the four known ivild races produce few and large tubers. 

 That the Papuan races produce large tubers, will be apparent to the 

 reader on glancing at the new plate. They number usually not 

 more than six. But the smaller tubers of the cultivated races are 

 much more numerous. The individual tubers of the wild races 

 have been weighed up to 2722 grammes or 6 lbs. 



In the races " Buga," " Tailukava " and " Deba," rootlets are 

 abundant upon the tubers ; but in " Memu " they are almost absent. 

 At maturity the flesh is stringy; but if eaten immature they are 

 palatable enough. Moreover a few tubers can be removed at a 



