PRESIDENT’S ADDRESS. 171 
horizons. How, then, does it come about that to this day 
we are unable to stace absolutely the age of our beds in 
European terms? The answer is plain. There was no 
uniform Tertiary fauna. There are resemblances in our 
recent fauna to that of the Northern Hemisphere, but there 
was no greater approach to uniformity in che early Tertiary 
times than exists at present. Then, as now, it was essenti- 
ally Australian in facies, and it is to Australian seas that we 
must look for affinities more than to the Tertiaries of the 
Northern Hemisphere. In saying this I would not blink 
the fact that there are genera, now extinct, which are repre- 
sented in the Tertiaries of both hemispheres, but the general 
facies of our early fauna is Australian, and in no way sup- 
ports the idea of a uniform Tertiary fauna, or anything 
approaching it, and the exponents of the Bipolar cheory 
must look elsewhere for an explanation. 
In considering the probability of the existence of uni- 
versal floras and faunas, it is necessary to define exactly 
what is meant by the terms. A few cosmopolitan genera, 
and even species, exist at the present day, but no oné on the 
strength of, say, the distribution of the genus Vatica, or of 
Lasea rubra, in recent seas, would for a moment think of 
suggesting a uniform recent fauna; and so it would appear 
to have been in the past. A few genera and species, with a 
long range in time, or with special means of dispersal. or 
want of plasticity, are widely spread, but side by side with 
these are many peculiar forms, characteristic of the region, 
and which do not pass beyond it. 
Naturally, the first forms to be examined and recorded 
in a new country are the familiar ones, and the lists pre 
pared in this way are apt to be misleading ; the resemblances 
are accentuated; the differences are barely noticed. In 
dealing with a collection of not too well preserved, fossils. 
how easy it is to succumb to temptation, and idencify, more 
or less definitely, some forms on their resembtances to already. 
described fossils, and to lump all the rest as unrecognizable. 
Let the paleontologist who is without sin among you cast 
the first stone. 
CORRELATION OF PERIODS. 
Huxley, in his presentation of the doctrine of homotaxis, 
suggested the possibility that a Silurian fauna in North 
America might be contemporaneous with a Devonian one in 
Britain; but probably he did not seriously believe in the 
possibility himself, and only suggested it in order to make 
the idea the more striking. 
