140 THE OCCURRENCE OP A GUM IN ECHINOCARPUS AUSTRALIS, 



ON THE OCCURRENCE OF A GUM IN ECHINOCARPUS 

 (SLOANEA) AUSTRALIS, BENTH. 



By J. H. Maiden, F.L.S., &c. 



This fine tree, usually known as " Maiden's blush " on account 

 of the colour of its timber, belongs to the Natural Order Tiliace?e, 

 closely allied, of course, to the Sterculiaceje and Malvaceae, many 

 of whose species yield gums. 



The Tiliacese are also all more or less mucilaginous, but I cannot 

 trace the record of a gum having been found on a plant, whether 

 endemic in Australia or not, belonging to this Natural Order. 

 Various Tiliaceous trees have their mucilaginous inner barks 

 utilized in India as demulcents, and doubtless in other parts of 

 the world, while that of an African species (Grewia mollis) is 

 stated by Barter to be used in soups, because of its mucilaginous 

 character.* 



The discovery of gum on Echinocarpus australis by Mr. Bauerlen, 

 collector for the Technological Museum, is therefore of interest. 



It was obtained from an old tree about 60 feet high and 3 feet 

 in diameter. The tree was somewhat injured by fire, but appeared 

 otherwise sound. Some younger trees close by, though not having 

 gum on to collect, showed signs that there had been some formerly. 

 The old tree also showed places where the gum had been dissolved 

 or washed away. 



The gum reminds one irresistibly of ox-horn. It contracts on 

 drying, forming transverse cracks, at which it breaks with a bright 

 conchoidal fracture. It cuts like horn. It is tough and tasteless 



* Masters in Oliver's Flora of Tropical Africa. 



