NEW SPECIES OF MANIHOT 



159 



two species is put at 500 to 1,000 grams per annum. The 

 rubber of M. dichotoma is, however, of better quality 

 than that of the other species. 



Seeds and plants of the three species have been 

 distributed by Kew to almost all the tropical British 

 Colonies, and the trees are at present undergoing trials, 

 in comparison with the Ceara tree, in many tropical 

 countries. It is, however, too early yet to pronounce 

 any opinion as to the respective merits of the different 

 species. 



In Ceylon M. dicliotoimi is being experimentally culti- 

 vated at the Peradeniya Experiment Station, three acres 

 having been planted with the trees at varying distances 

 apart, 20 by 20 ft., 12 by 12 ft., 8 by 8 ft., and C by 6 ft. 

 The results so far are very promising, as the species appears 

 to thrive better than M. Glaziovii. The chief defect is the 

 extreme brittleness of the tree, the tops being very liable 

 to damage by wind, and belts of other trees would therefore 

 be requued as " wind-breaks " in cultivating the tree. 



Recently a number of the M. dichotoma trees in Ceylon 

 were tapped for the first time and the rubber obtained 

 was exammed at the Imperial Institute with the fol- 

 lowmg results : 



Ash 



2-9 



The msoluble matter consisted of fine particles dis- 

 tributed through the sample, and owing to the soft char- 

 acter of the rubber it was found impossible to ehminate 

 the impm-ity by washing. The rubber is of very fair 

 quality so far as composition is concerned, and the physical 

 properties may unprove as the trees increase in age. 



