CHAPTER VIII. 



LATEX. 

 FUNCTIONS OF LATEX. 



SEELIGMANN remarks:* "India-rubber is a hydrocarbide of a 

 vegetable nature, extracted from the juice secreted by the 

 protoplasm of a so-called primordial cellular tissue of a great 

 number of trees, shrubs, and bindweeds of hot countries. The 

 principal trunks of this tissue are situated in the internal zone 

 of the bark, outside the liber of the bundles and their sclerose 

 sheath when it exists. They send out numerous branches, some 

 outwards, across the bark to the epidermis, where they terminate 

 in a cul-de-sac ; the others, less numerous, towards the interior 

 cross the endodermis and the medullary rays, to the pith, 

 around the periphery of which they diverge longitudinally. 

 This carbide of hydrogen and its derivatives, the issue of the 

 activity of the protoplasm, would not appear, at least according 

 to certain naturalists, to be afterwards re-employed in the life of 

 the plant, and is considered by them as a product of elimination, 

 a reserve product, utilised by man in the arts and industries. 

 Other men of science to whom we readily give in our adherence 

 consider this carbide necessary, at least partially, to the life of 

 the plant." 



Scott decided, after investigating the laticiferous system of 

 young Hevea seedlings from one to twenty-five days old, that 

 the laticifers are definite vessels which have partition walls. 

 The latter soon become absorbed, leaving continuous tubes. 

 They are only found on the bast side of the cambium, from which 

 they are formed in a continuous network. Latex is considered 

 by some authorities to be excretory matter of no further use to 

 the plant, so that if the whole of it could be extracted without 

 damaging the plant's structure, no harmful results to its health 



* " Le Caoutchouc et la Gutta Percha." 



