Gums, Resins, 344 [June 190?. 



is Loranthus theobromae, which is found in the region of the Amazon, in British 

 Guiana, and Venezuela. It is a very common parasite, and grows on Inga, mango, 

 and especially on cacao and coffee. It has clasping air-roots. Unripe fruits gave 

 5 to 10 per cent, of pure rubber, which would mean about twice this percentage 

 from the dry fruits. It is intended to propagate this mistletoe in Venezuela on 

 abandoned cacao and coffee plantations, due coffee plantation already produces 

 four times as much mistletoe berries as coffee from the natural spread of the 

 parasite. It is reckoned that several thousand tons of wild mistletoe rubber may 

 be obtained in the next few years from Guiana, Venezuela, and Brazil. 



These parasites can easily be planted on shade trees, etc., by leaving ripe 

 fruits for two weeks in the shade, aud then placing them in cuts in the bark of the 

 host plants. The smaller mistletoe, L. theobromae, only needs for propagation that 

 a piece of stem, with sucking roots, shouid be stied to a branch of the host plant. 



A Non- Rubber Yielding Hevea. 



By Ivor Etherington. 



It is a generally conceded fact that the latex of other trees than Hevea 

 brasiliensis is often employed by the rubber collectors in Brazil to increase the 

 bulk of the products. One authority mentions Mimusops etata (the Macandaruba 

 tree). The adulteration of Para rubber by this latex.it is stated, " might account 

 for the great differences that have been occasionally observed in the behaviour 

 of Para rubber in certain stages of manufacture, the coagulated juice of the 

 Mimusops genus resembling gutta percha rather than caoutchouc." Sapium 

 aucuparium is also said to be largely used as an adulterant. The latest addition 

 to cur information on this subject is a contribution to "Journal d' Agriculture 

 Tropicale" by Monsieur O. Labroy, who has been doing fruitful botanical research 

 work at Manaos (Brazil), the centre of the rubber industry, for a year. Labroy 

 states that the latex of Hevea discolor, Muell. Arg,, cannot be coagulated to give 

 rubber, but that it is vised to adulterate latex from good rubber trees. 



Of this Hevea he says: " Prolonged observation of these trees have shown 

 me that they are incapable of yielding a product of any value. Some of them, 

 tapped at different times, have only given a small quantity of uncoagulatable 

 latex. Repeated tapping of young specimens (5 to 7 years of age) and others of 

 mature age (trunks measuring 39 to 58 inches in girth), growing on the banks of 

 quiet rivers where only they appear to flourish, gave the same negative results. 

 These proofs notwithstanding:, I showed the Heveas in question to two men well 

 versed in rubber exploitation from the lower Rio-Negro ; they did not hesitate 

 to assure me that they were only ' seringueira barriguda ' ; that is to say of no 

 interest from the point of view of latex yield. They had, however, seen them used 

 in Rio Madeira for adulterating the latex of good rubber trees." 



Labroy seems to be a little doubtful as to whether the trees he found in 

 the Manaos district were the real Hevea discolor, found by Martius and Spruce 

 in the same region, aud by Ule in the middle Rio-Negro. Botanically the trees 

 are the same ; the only difference being in the size and height of the tree and the 

 dimensions of the leaf, Those under observation at Manaos were 33 to 48 feet 

 in height, a straight trunk bare of branches for 18 to 24 feet from the ground ; the 

 main branches being little ramified and rather spreading, 



" It should be noted," he says, " that the fruit and seeds are exactly alike as 

 possible to those in the illustration given by M. Jumelle in his lecture ' Les Plantes 

 a caoutchouc et a gutta,' from specimens of ' seringa barriguda ' brought from the 



