264 



wet season. Similarly the trees on the outskirts of a ' teo-non 

 wood yield less but more concentrated latex. At the end of May 

 Dr. Eberhardt obtained from a single tree of 20 cm. in diameter 

 as much as 480 grammes of latex; but he thinks that in the 

 autumn this tree might well have yielded 600-650 grammes. He 

 recommends tapping at the base of the trees as the latex taken 

 from the young parts does not coagulate. In this respect the 

 ' teo-non ' behaves like Ficus and Castilloa. 



Dr. Eberhardt obtained 676*6 grammes of caoutchouc per 

 kilogramme (or 67*6 per cent.) from two litres of latex. The best 

 method of inducing coagulation was by means of sulphuric and 

 hydrochloric acids; acetic acid seems to impair the natural 

 cohesiveness of the caoutchouc globules. Heating directly over 

 fire results in an inferior product; as it has to be continued 

 until the serum is completely evaporated when a succession 

 of thin and tough skins is formed which do not adhere 

 to each other. On the other hand, the hot water bath gives 

 excellent results. The treatment with sulphuric acid, however, 

 seems to be by far the best process and the caoutchouc thus 

 obtained is of first-rate quality, very strong (nerveux), resistant 

 and elastic. Mr. Cibot, an expert in American rubber and in the 

 rubber industry generally, states that the 'teo-non' rubber is 

 equivalent to Para and practically indistinguishable from it. A 

 native-made cake of 'teo-non ' rubber was, in fact, awarded a gold 

 medal at the French Colonial Exhibition at Marseilles in 1906, in 

 spite of the usual impurities present in the native article. 



A score of young plants are at present in cultivation in the 

 Botanic Garden at Hanoi. Only one member of the small subtribe 

 Xatoneae, to which Bleehrodea belongs, has been found up to the 

 present in India, viz. : PseudostreUus indica, Bur., a small tree 

 oi the Khasia Hills ; but between them and Tonkin, there must 

 be many localities where the ' teo-non ' could be grown with 

 success if it should be found that its natural area does not extend 

 into British territory. 



The following description is based on the specimens received 



5°? frr r °> an d saPPlemented from the description given by 

 Messrs. Dubard and Eberhardt :— 



w SS 3 2~ 5 i° fee } high ' copiously branched, with whitish 

 Sri v! * k ? nd "S ite wood * branchlets scaberulous from 

 obW r, \i ng *T llae - I**™ very polymorphic, obovate- 



oblong to onlan^polafp m. i™^~i«.l~ _v„„ *,, K 7 -. . * _ ^ 



ZtlviL i i " tat ^ 8 ° metl ™s with three coarse teeth on each side 

 b" " ?? l e Tf dle , and the acumen ' rarel y alm <*t entire, 2-6 ins. 

 loonV wiS fh ne ?" Ve8 5 " 10 on each side > curved, joined in 



S- neHoli «l^ rgin ' V6ry 8lender ' network of ™ ins ver y 

 #i lin P fnni J? 1 ^' Very SCabrid from white rigid papillae, 

 Asexual cv™, ? monoecio » 8 > ™ small axillary, uni- or 

 cinders of HflL male CJ T S formin g 8ma11 compact globose 

 bractlets obtl ST*' f 6 "? 6 or s^bsessile, bracteate; bracts and 

 SSfA *1 m b « r ° ad ' the inner narr ™, as long as or 

 ■t^^^^SSSS *™?> f , emal « cymes subsess'ile or 



apex bv twn hrn^ ^ * »Y. . icmaitJ nower, embraced to tne 



apex by two broad ovate or elliptic, obtuse, scaberulous, bracteoles, 



