ie 
MOORE—-AUSTRALIAN MESOZOIC GEOLOGY. I 
age, a fact which is now generally recognized, whilst by others they 
were referred to the Jurassic or the Triassic period*), the first 
positive evidence that was made known of any fossils of Mesozoic 
age was through the researches of F. T. Gregory, Esq., who, in a 
paper on “ The Geology of a part of Western Australia,” communi- 
cated to the Society by Sir Roderick Murchison, and published in 
the Quarterly Journal, vol. xvii. 1861, p. 475, notices the presence 
of what he considers Cretaceous rocks in that district. The group, 
he remarks, partly consists of chalk-like rocks and ferruginous sand- 
stone, containing Ammonites, Zrigoniw, and Pectens. “The bed of 
the Greenough river,” he states, ‘‘is the best spot for procuring speci- 
mens, although a few are to be found in the chalk-hills near Gingin 
(spines of Echinoderms &c.).” The specimens exhibited at the read- 
ing of Mr. Gregory’s paper are now in the possession of the Geological 
Society, and consist of a single cast of Trzgonia Moorer (Lycett), and 
avery much worn Pecten, of uncertain species, both evidently of Oolitic 
age. They were accompanied by a Ventriculites in flint, and a portion 
of a chalk Ammonite, and also by a considerable number of specimens 
of the age of the Carboniferous Limestone. 
Meagre as was the evidence thus afforded, it was still sufficient 
to show, for the first time, the presence of two groups of Mesozoic 
rocks, the Oolitic and the Cretaceous, in Western Australia. 
It is not improbable, from the remarks of Mr. Gregory, that the 
latter are in situ; but hitherto we have no record of the actual pre- 
sence of stratified Oolitic beds. It is probable that the two speci- 
mens may have been obtained from the bed of the Greenough River, 
as they are evidently drifted fossils, a character which will be found 
to be general with other remains to be hereafter noticed. 
The next, and, up to this time, the most important notice con- 
nected with the Mesozoic Australian fauna was due to the Rey. 
W. B. Clarke, and related to the discovery, by Mr. Gordon, in the 
neighbourhood of Wollumbilla, of a large number of organic remains 
which will be more fully noticed hereafter. These were to have been 
in England in time for the last Exhibition, but had not then arrived. 
In that Exhibition, however, there might have been noticed a set 
of fossils, forwarded by Mr. Shentonf rom the Greenough Flats and 
other districts of Western Australia, which were not only the most 
numerous but the best-preserved Australian secondary fossils that 
had yet been publicly exhibited in this country. These consisted of 
Ammonites macrocephalus, Belemnites canaliculatus, Trigonia Mooret, 
and species of Ostrea, Lima, Astarte, Cucullea, Myacites, Rhyncho- 
nella, &e., all evidently of Oolitic types, and identical with species 
that will be noticed below as occurring in Mr. Sanford’s collection. 
I could not open the cases to give them a very critical examination ; 
but there appeared to be about fifteen species in the series, together 
with fossil wood, apparently from the same formation. In addition 
to the above, there was a siliceous cast of a Micraster from the chalk, 
and some vegetable impressions in a cherty sandstone, the age of 
which I could not recognize. I had hoped to secure these fossils, 
* See W. B. Clarke, Quart, Journ, Geol, Soe, vol, xxiii. p. 11, 
