PRESIDENTIAL ADDRESS. 23 
have, now proceeding, perhaps, evidences of the influences 
which in the dim past have largely been responsible for the 
original establishment of the numerous species and groups 
of the genus, which have thus become not only divergent 
but progressive. 
It seems then not unreasonable to consider that if 
sufficient time were allowed for the completion of the 
changes now proceeding that the several groups of the 
genus Hucalyptus, as we know them to-day, would eventu- 
ally establish themselves as new genera of the Myrtaceeze. 
Hooker, in his Flora of Tasmania, evidently felt a 
difficulty in discrimination, because, when writing from the 
botanical standpoint, he says, ‘‘that it is much easier to 
see peculiarities than to appreciate resemblances, and that 
important general characters which pervade all the mem- 
bers of a family or flora are too often overlooked or under- 
valued.”’ 
To assist in the endeavour to attach their true value to 
these important general characters of the genus Kucalyptus 
is, [ am sure, the ambition of all workers upon these 
scientifically interesting and economically valuable trees. 
The genus Angophora furnishes considerable evidence, 
both botanically and chemically, in the direction of showing 
that the Corymbosece is perhaps, the oldest of the many 
groups into which the genus Hucalyptus divides itself. The 
venation of the mature lanceolate leaves is the same, the 
chemical constituents of the essential oils are similar, the 
exudations are in agreement, and the general morphological 
features have strong resemblances, excepting, of course, 
the important character of the Eucalypts, the operculum. 
The genus Angophora is probably a very old and perhaps 
a decaying one, and originally may have had a much more 
extensive distribution in Australia. It does not appear to 
have had the power to adapt itself generally to the changing 
