49 



Haucornia speciosa (Mangabeira Rubber) is a slender 

 growing tree fairly abundant over nearly all Brazil from 

 Pernambuco to Peru. Unlike the Heveas it grows in poor 

 soils, and up to an elevation of 5000 feet. In some parts 

 of Brazil the latex is diluted with water and as the particles 

 of caoutchouc coagulate it is skimmed and dried. At Per- 

 nambuco coagulation is obtained by the addition of alum, 

 and in Peru — soap-suds, in other parts common salt is 

 used for clotting the latex, but with any of these methods 

 Mangabeira is imperfectly, and in fact, only partially coag- 

 ulated and frequently ferments giving off an offensive 

 odour, and there is also a heavy loss of weight (from 

 40-50%) in washing. There appears to be a fair supply 

 of this rubber, valued at 3/1.-J- against 5/4 for standard 

 market price, no doubt it would be much improved if coag- 

 ulated by centrifugalising as is done with Castilloa. 



Forsteronia gracilis is a climbing plant native of 

 British Guiana, North Brazil, and Venezuela. The rubber 

 reported has been fine grade and the cultivation of the 

 plant in the West Indies is expected. I would however 

 again remark that the cultivation of climbing rubbers has 

 not so far met with success. Another species F. floribknda, 

 is found in Jamaica and is also said to produce fine grade 

 rubber. 



The Indo-Malayan Apocynaceae are well represented 

 by the genus Willughbeia* (getah gerip, singarip, getah 

 susu, and many other names according to locality). The 

 best rubber is obtained from W. firma, formerly common 

 in British Malaya, Sumatra, and Borneo. The rubber is 

 obtained by ringing the liane and the latex drops into fold- 

 ed palm leaves, or native cups, and is coagulated with alum 

 or salt when slightly heated. In this form the rubber is of 

 poor quality — very wet, and loses from 40-50% in washing 

 and at the present time is worth about 2/9. What is now 

 supplied comes principally from Borneo but the output has 

 largely diminished from all sources. A few years ago, in 

 Malacca and in the F. M. S. getah gerip or Willughbeia (of 

 sorts) was used by natives for adulterating getah percha 

 and getah taban. 



Other species are: — W. coriacea, W. tenuiflora, and 

 W. flavesceMs, and the Bornean rubber is a mixture of any 

 or all of these, and probably other rubber vines too. None 

 of these rubber vines have been successfully cultivated in 



* In Malaya, the Peninsula, Java, Sumatra, and Borneo the generic term 

 of gutla or getah is applied to all elastic gums. 



