PLANTS PRODUCING GUMS AND RESINS 329 



Acacia ataxacantha. — A branching shrub, very common in Senegal^ 

 2 to 4 metres liigh, with short curved spines and whitish flowers in 

 cylindrical spikes. It produces small quantities of a whitish gum. 



Acacia fasciculata. — According to M. Chevalier this acacia is 

 extremely abundant in the desert regions of Northern Africa. The 

 whitish flowers emit an exquisite perfume. 



The gum, which is fairly abundant, is unfortunately of inferior 

 quality, being only partially soluble. In colour it varies from white 

 to reddish, and it collects in mammillated masses. 



Acacia Farnesiana. — Largely cultivated in the South of France on 

 account of the delicate aroma of its flowers, of which great use is 

 made in perfumery. It is a large shrub, originally a native of San 

 Domingo, whence it has been introduced into India. In the West 

 Indies it is called the fragrant acacia and in Reunion the yellow cassia. 



It produces a fairly large quantity of gum, which, in some pro- 

 vinces, is collected. In Tenasserim it yields a gum which Masson 

 says has all the properties of gum arable; it occurs in roundish, 

 transparent tears, which are soluble in water; according to Waring it 

 is a first-class product. 



Acacia decurrens. — In Australia, Maiden says, this shrub produces- 

 an abundance of gum during the hot season. Its colour varies from 

 yellow to dark amber. According to the same writer, it is scarcely 

 soluble in cold water. 



After examining a sample of this gum from India, de Cordemoy 

 concludes that when broken up into small pieces it dissolves in cold 

 water both rapidly and completely. The solution is cloudy, but 

 after filtration a pale yellow, clear mucilage is obtained, which is 

 perfectly adhesive. 



De Cordemoy adds that it is hard and horny, and the colour is 

 not uniform, being pale yellow, or grey and semi-transparent in some 

 parts, and reddish in others. 



Acacia dealbata. — A native Australian tree which, according to 

 Maiden, yields an excessively viscous gum. 



It is reddish in colour, with a light-coloured fracture, and may 

 be collected in fairly large quantities. 



Heckel and Schlagdenhauffen have analysed it, and found it com- 

 pletely soluble in water : — 



Hygroscopic water ... 

 Non-volatile salts 

 Tannin 

 Gum arabic 



Samples from Reunion, where this acacia has been acclimatized, 

 took the form of large, irregularly spherical tears, dark red in colour, 

 with a dull fracture. This gum is only partially soluble in water 

 and contains from 8 to 10 per cent, of insoluble gum. De Cordemoy 



