8 
co-element, developed already in Pliocene times a series of peculiar genera, 
which, however, again disappeared on the advent of the present epoch. 
At the same time, the second question, as to the relations between the 
Australian forms of plants in the European Tertiary Elora and the Australian 
Tertiary plants, is answered also. The first-named form only a co-element of 
the flora, the latter embraces several floral elements, of which only the 
principal can be compared to the former. That the non- Australian indigenous 
forms of plants (co-members) of the living flora of Australia arc gencrically 
to be referred to the co-elements of the Tertiary Elora, has already been 
shown, and thus the third of the questions propounded above has been 
answered also. 
Before I proceed to the description of the fossil plants, I must notice 
briefly the localities whence they have been obtained. 
(a.) Dalton, near Gunning, New South Wales. 
The fossil plants of this locality are found in layers of clay, sand, and 
marl, which arc ferruginous. Similar strata occur also in New England.* 
Mr. C. S. Wilkinson regards these strata as at least Lower Miocene. The 
rocks of these formations, on account of their coarse and siliceous nature, are 
not very favourable for the preservation of plant remains. As the leaf- 
impressions arc nevertheless very distinct, it is to be assumed that the leaves 
must have been of a very firm and leathery texture. I have determined 
twenty-seven species of fossil plants from this locality, belonging to seventeen 
orders and twenty-one genera. Of peculiar interest is the Fteris Humei, a 
species discovered by Mr. J. K. Hume, and analogous to the P. tremula, 
which is still living in Australia; a species of Alnus ; four species of Oak, 
among which Quercus Dancini, related to Q. bidens, Hcer, from the Tertiary 
of Sumatra, and Q. Hooker i, corresponding to Q. laurophylla, Goeppert, from 
the Tertiary of Java ; Fa (jus Willcinsoni , a beech, intermediate between a 
species found in the Cretaceous and another Tertiary species ; a Castcmopsis, 
analogous to the Eocene C. mephitidioides. Gey. sp., from Borneo ; two 
species of Clnnamomum, analogous to species from the European Tertiary 
Elora ; a species of Laurus analogous to the Tertiary L. Swoszowiciana ; a 
* Vide Mines and Mineral Statistics, 1875, p. 87. 
