AUSTRALIAN VEGETABLE EXUDATIONS. 399 
Acacia retinoides, Schlecht. (N. O. Leguminosw). 
Sample from Victoria, kindly sent by Baron von Mueller, 
This gum is in tears of an amber colour, transparent, bright 
and somewhat brittle. It dissolves entirely in water, the solution 
being slightly tinged with brown. It is fairly adhesive being of 
good viscosity. It gives a slight precipitate with ferric chloride, 
and slightly darkens to a lemon colour when heated with dilute 
soda. It may be considered a promising specimen of the arabin 
gums, unfortunately the specimen we have is too dark in colour 
to be of first rate quality. The other tests, usual with a gum of 
this class, were not carried out on account of the small amount 
of material at our disposal, as a portion was required for permanent 
display in the Gums Collection in the Technological Museum. 
Acacia Bakeri, Maiden (N.O. Leguminose). 
Collected at Mullumbimby, N. 8. Wales. 
Our specimens of this gum are principally in tears, very bright 
and transparent, dark amber coloured, very brittle and bright in 
fracture, It is entirely and readily soluble in cold water, and is 
in this respect one of the best of the coast Acacia gums of this 
Colony ; it is very adhesive and its comparative viscosity is high. 
Unfortunately our samples darken much in aqueous solution. 
The solution is slightly acid to litmus paper. Ferric chloride gives 
*cream coloured solid mass exactly resembling in bulk and colour 
that from A. Maideni, and it behaves in the same way as that 
gum with a saturated solution of borax, mercuric chloride and 
basic acetate of lead. Both these gums belong to the arabin 
Sroup, and if obtainable in quantity would be of some commercial 
Value. As far as our samples show at present, the gum of 4. 
Maiden has a better colour than that or A. Bakeri, but it is 
inferior to it as regards its adhesive properties. When warmed 
With dilute soda solution, the aqueous solution of the gum darkens 
*onsiderably - The ash of this gum is remarkable in that it con- 
icc large proportion of manganese. It contains 15-2 per cent. 
and 3-6 per cent. ash. von 
