246 M. B. WELCH. 
or caustic potash than the Brush-Box, and little trouble 
was experienced in separating them. Another test is by 
burning the shavings, since the Turpentine goes out as 
soon as the flame dies down, whereas the Brush Box 
smoulders to a grey ash. 
It was thought probable that the age of the speciméns, 
i.e., the time elapsed since felling might affect the colour 
reactions to some extent. In the case of H. tereticornis, 
the timber giving a marked colour with ferric chloride was 
obtained in 1916, whereas the specimen giving practically 
no colouration was felled in 1907, the two localities being 
widely different. On the other hand, E. propinqua obtained 
in 1895 gave a darker colouration with ferric chloride than 
timber felled in 1910. Again, a specimen of EH. robusta 
giving a dark extract was obtained in 1913, whilst a speci- 
men from a tree felled in 1916 gavea much lighter colour- 
ation. The conclusion arrived at in regard to age after 
felling is, that it has no definite general effect in any one 
direction, although it may possibly affect the behaviour of 
any one species. 
Comparing the sizes of the trees and therefore the ages, 
assuming the rates of growth to be approximately equal, 
it was found that, whereas the more recent specimens of 
E. robusta which gave the lighter colourations were 
obtained from a log three feet in diameter, the darker 
colours were from a log only 16 inches in diameter. On 
the other hand, in the case of EH. propinqua, the darker 
colour reactions were obtained from a log three feet in 
diameter. Itis evident from these two cases that the size 
or age of the tree has apparently little effect. 
To compare the timber of different periods of growth in 
the same tree, extracts were prepared from near the heart, 
and also from near the sap-wood of H. tereticornis, in both 

