382 PROCEEDINGS OF SECTION B. 
The fractures are quite bright. It has no odour. To cold water 
it imparts a dark, rich orange-brown colour; at the same time, 
the insoluble portion forms a bulky gelatinous mass. 
In bulk, the gum of C. afefalum appears in no way different 
from that of C. gummiferum. It, however, smells more or less 
strongly of coumarin, which is also contained in abundance in 
the bark. It is obtained either by wounding the tree or by 
felling it. In cold water it swells up largely, and at the same 
time possesses a good deal of coherence. It imparts to the water 
a pale orange-brown colour and an intense odour of coumarin. 
Ceratopetalum gums are kinoid or astringent. They are much 
of the colour and texture of ruby kinos,* but unlike those 
substances, swell up and only partially dissolve. They may be 
described either as £zvo0s or as kinoid gums. All the definitions 
of kino with which I am acquainted allude to the tannic acid 
contained in them, and make no allusion to any gummy consti- 
tuents. All the gum of kinos of Zuca/yptus known to me is readily 
soluble in water, and is arabin ; but in the case of Ceratopetalum, 
the gum is present in the form of metarabin. Whether that 
circumstance is sufficient to remove them from the kinos is a 
matter of opinion; in any case they form a connecting link 
between the kinos and metarabic gums. If they be looked upon 
as kinos, I believe the present is the first instance in which such 
substances have been recorded from the Saxi/ragee. 
Ceratopetalum gums form a remarkable group, and at present 
I do not know any other precisely similar gums. C. afetalum is 
worthy of note as an available source of coumarin, and the 
presence of that substance sharply separates the two gums. The 
following difference also appears to be constant. The ash of 
C. gummiferum is quite white, while that of C. apfetalum is dark 
brown, very bulky, and difficult to ignite. It contains but a 
small percentage of iron, but manganese is abundant. The 
composition of the gums may thus be stated :— 
C. Gummiferum. C. Apetalum. 
Tannic acid (estimated as 
gallo-tannic acid es 
Phlobaphenes (soluble in 8% 
alcohol)... be 19°5 ste 12:21 
Phlobaphenes (insoluble 
in alcohol, together 
16:76 moe 6°35 
with metarabin) ae 41-6 as 52-09 
Coumarin so “ih nil (variable) 2 to 3 
Accidental impurity... 2:5 ee 2°0 
Moisture ae Re 16°7 eee 20°47 
AGH... Jn - 1.8 oe 3°44 
98-86 99°56 
* See papers by the author, Pharm. Journ., [3] xx. 221, 321, and Proc. Linn, Soc., N.S.W. 
July, 1889. 
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