71 



may be assumed, too, that location and environment influence to some extent 

 the formation of the tannin, as the moss-grown barl< is less rich. To obtain the 

 required data to decide these points, a considerable amount of work would be 

 necessary, although these, and similar problems, would not be difficult to solve. 



With C. glaiica there does not appear to be the same variation in the 

 amount of tannin deposited under varying conditions, as with C. calcarata, because 

 a specimen from a medium-sized tree, collected at Narrandera, New South Wales, 

 n March, 1909, gave 14-7 per cent, tannin ; a very thick bark collected at the same 

 place in April, 1907, gave 14-6 per cent, tannin; and a bark from a medium-sized 

 tree, collected at Narrabri, New South Wales, in June, 1909, gave 10-5 per cent, 

 tannin. 



Pilot. C F. Lflstr)'")!. 



A " Pine Ridge," showing how CalUtris calcarata grows on Hills, 



MiCHELAGO, N.S.W. 



The thick barks of C. calcarata and C. arenosa were readily powdered, 

 although shortly fibrous, and the greater portion of the tannin was easily extracted 

 from them with cold water. \\'hen the final extraction had been made with hot 

 water, the amount of non-tannins increased somewhat, although it was still com- 

 paratively small, but the tannin had not increased in proportion. The Hquor 

 had darkened by the hot extraction, as a larger proportion of the red constituents 

 of the bark had been dissolved. When cold water alone had been used, the colour 

 was very satisfactory. By this method, too, only a very small amount of sub- 

 stances other than tannin was extracted from the powdered bark. 



