PROCEEDINGS OF SECTION B. 93 



the two genera. Broadly, Angopliora exudations are 



allied to those of Class II,, of eucalyptus kinos, but are 



more in agreement with the members belonging to the 



intermediate section with a high astringency value ; they 



•contain Aromadendrin but not Eudesmin, which peculiarity 



is also characteristic of eucalpytus exudations at this end 



of the genus. It thus appears that the kinos of the earliest 



eucalyptus species contain mixed tannins, as well as 



some of the other constituents now found in greater 



.quantity in other species or classes. The increases of 



constituents in one direction or another thus followed the 



evolutionary development of the genus, until the maximum 



amount was reached in one or two species, as, for instance, 



Eudesmin in the kinos of the typical " boxes," and the 



glucoside in those of the typical " ironbarks." The kinos 



which fall into Class I. appear, therefore, to indicate 



descent from earlier species, so that the eucalypts which 



yield oils rich in phellandrene, and also kinos which fall 



into Class I., represent those belonging to the most recent 



section of the genus. The evidence so far obtained from 



the study of the kinos supports the conclusions arrived at 



by Mr. R, T. Baker, F.L.S., and myself, and announced in 



our work, A Research on the Eucalypts, published in 1902. 



(e) As the possibility of profitably utilizing eucalyptus kinos 



commercially is naturally of importance, the following 



conclusions may be stated : — 



Eucalyptus kinos of Class I. do not appear, from our present 



knowledge, to have much commercial value, unless their remarkable 



gelatinizing property can be turned to profitable use. Kinos belonging 



to Class II. might be used for tanning purposes if obtainable in quantity, 



especially those intermediate between Class II. and Class III., and 



some of those in Class III also. Their chief value, however, lies in the 



fact that they indicate the possibility of satisfactorily utilizing, for 



tanning purposes, the barks of species which yield them ; providing, 



of course, that the tannin is present in sufficient quantity to enable 



them to be used directly, or to be utilized for the manufacture of 



extracts. The exudation of E. occidentalis, the species which furnishes 



the " mallet bark " of Western Australia, now so largely used for 



tanning, gives a green colouration with ferric chloride, and altogether 



falls into the intermediate section with the lower astringency values. 



It would be well, therefore, to determine the tannin values of the 



most likely barks of those species which yield similar exudations. 



The kino of E. calophylla, the " red gum " of Western Australia, 

 shows considerable commercial possibility, and an excellent tincture 

 for pharmaceutic:! purposes can be made with it, one that does not 



