PROCEEDINGS OF SECTION B. 381 
3._OBSERVATIONS ON THE GUMS YIELDED BY 
TWO SPECIES OF CERATOPETALUM. 
By J. H. Maney, F.LS., F.C.S., Curator of the Technological 
Museum, Sydney. 
THE genus Ceratopetalum belongs to the natural order Saxifragee, 
and is endemic in New South Wales. Of its two species, the 
first is C. gummiferum (Smith), generally of bushy size, though 
in favourable localities it attains the dignity of a small tree. It 
is the well-known ‘“Christmas-bush” of Sydney, and its reddish 
persistent calyxis very showy. For this reason it was also called 
‘‘ officer-plant”” in the early days of the colony, though an 
officer’s tunic is of a very different colour. The second species is 
a well-known gully tree, never found out of moist situations, and 
is tall, with smoothish bark, bright#looking foliage and white 
flowers which it bears in abundance. This is C. afpetalum 
(D. Don), and its local names are “ coachwood,” “ lightwood,” 
and “ leatherjacket.” 
In deseribing C. gummiferum, Dr. J. E. Smith, in “ A Specimen 
of the Botany of New Holland” (1793), gives an excellent figure 
of the plant, which he calls the ‘“ three-leaved red-gum tree.” 
He says :—‘‘ This, Mr. White informs us, is one of the trees (for 
there are several, it seems, besides the ucalyptus resinifera) 
which produce the red gum. He further remarks that it is the 
only wood of the country which would swim in water.” (The 
latter statement is, of course, founded on imperfect knowledge.) 
This is the first and, as far as I know, the only reference to the 
gum-yielding propensity of this plant; but it impressed Smith 
sufficiently for him to give the specific name he did. Mr. White’s 
observation, so early recorded, does not seem to have attracted 
the attention of subsequent observers. 
The first parcel of C. gummiferum gum I received was in small 
tears of a beautiful ruby colour, perfectly transparent, and having 
a bright fracture. It is powerfully astringent to the taste, sticks 
to the teeth, and obviously contains a large proportion of gummy 
matter. This sample was removed from the cut ends of a log, 
from which it exuded in small drops and in thin pieces which 
dried very quickly. The tree was 6 to 9 inches in diameter. It 
seems, as far as our experience goes at present, that ring-barking 
or wounding the tree, or even cutting it down merely, is of little 
avail to obtain the gum ; the tree must be cut into logs or pieces, 
so that the timber is open at doth ends, before the gum will exude 
in any quantity. It remains to be seen whether the gum exudes 
most freely in the summer. 
I have received a cake of the substance obtained by draining 
the ends of a severed log on to a plate. When first received it 
was exceedingly tough; but on exposure to the air for two or 
three months, it fractured without difficulty between the fingers. 
