GUMS, KESINS, AND OTHER VEGETABLE EXUDATIONS. 193 



Ficus rubiginosa, Desf., "Port Jackson Fig." 



This fig, like others of the genus, exudes a juice when the bark 

 is wounded. It is put to no useful purpose. It has formed the 

 subject of De la Rue's and Miller's chemical investigation (73). 



The official catalogue of the N.S.W. Exhibits (Paris 1855), con- 

 tains the following information in regard to this particular 

 specimen: — "Perforated waxy substance, exuded from the bark of 

 native fig Ficus ferruginea" (an obsolete name, and the substance 

 is attributed by Sir William Macarthur to F. rubiginosa), exhibited 

 by W. Stephenson, Esq., Surgeon. From the Manning River. 

 "A remarkable substance, possessing the properties of gutta- 

 percha and bird-lime combined, and which can be obtained in the 

 colony in any quantity. It softens by heat like gutta-percha, and 

 like that substance can be moulded while warm into any shape, 

 which it retains when cold, but becomes brittle. When very hot 

 it is so strongly adhesive that it cannot be touched by anything 

 without sticking most obstinately to it." 



Mr. P. L. Simmonds said of the specimen, "An elastic gum- 

 resin from an Australian Ficus was shown at the Paris Exhibition 

 of 1855 in the New South Wales collection, in small tears of a 

 dingy appearance, which might prove useful. A large portion 

 dissolves in warm linseed oil, but spirits of wine does not act 

 readily upon it. By mastication it becomes tenacious and bleaches 

 thoroughly." 



From the above and from statements in the original paper 

 there is no doubt that the substance acted upon was picked 

 already dried from the trees, and, on account of the delay in 

 experimenting upon it, it was a very old specimen when analysed. 

 I procured a small quantity of the milky juice (latex) of this 

 species, and obtained it quite fresh. It was obtained in the 

 spring by auger holes well through the bark. Whether a tree 

 will yield any liquid at a particular time is very uncertain, and 

 can be ascertained only by tapping. It apparently in no way 

 differs from the " Moreton Bay Fig " juice (F. macrophylla), so 



M— Dec. 4, 1901. 



