Western Australia. — Like the organic remains sent by Mr. Shenton to the Exhibition in 1862, those forwarded by Mr. Clifton to Mr. Sanford were unfortunately unaccompanied by any precise description of the beds, or the locality from which they were derived. Mr. Sanford informs me he believes the latter were obtained near either Shark's Bay or Champion Bay, "Western Australia, his strong impression being that they are from the former locality. In this case their locality would be nearly 150 miles north of the Greenough Flats, from which districts the specimens sent by Mr. Shenton to the Exhibition were said to have come. Mr. Sanford also informs me that a soft limestone deposit extends in this district for some distance nearly parallel with the coast, lying on older gneiss and Palaeozoic rocks, which, in the interior, contain copper and lead. He believes, from information he received, when in the colony, from Mr. Gregory and others, that this limestone may also be found in many places on the coast itself*.
On first examining the specimens from Western Australia, I at once observed that their matrix presented different lithological characters, such as might be expected to occur with remains derived either from various beds in the same geological formation, or still more probably should they have been obtained from formations of different geological ages. Mere lithology is not always a safe guide, and the less so when beds have to be correlated from points so wide asunder as Australia and England : but in this instance there could scarcely be a mistake ; and even had no distinctive fossils been present, a geologist acquainted with the secondary rocks of England and Europe could hardly have failed to refer the greater number of the specimens to the horizon of the Lower Oolitic rocks. Associated with these were Upper-Lias species, whose matrix was perfectly identical with a ferruginous or variegated limestone of the Upper Lias occurring near Bath, where it is only about two feet in thickness. And the Middle Lias or Marlstone was not left unrepresented ; for from this formation Myacites liassianus, Quenst., and a Pholadomya occur.
The Middle Lias is the formation from which, in the north of England, such an enormous quantity of iron is being manufactured, the beds yielding an average of 32 per cent, of metallic iron. It is not a little remarkable that this comparatively thin horizon of the earth's crust should, at the antipodes, present similar mineralogical conditions. I have had portions of two of the blocks analyzed ; one of them gave 49 and the other 56 per cent, of metallic iron. In this way, lithologically, and almost without the evidence of the fauna they contain, the Western-Australian specimens might be decided to be contemporaneous with the Lower Oolites and the Upper and Middle Lias of this country, from which they are 16,000 miles separated.
The separate blocks or specimens in my possession from Western Australia arc about sixty in number, and include many duplicates
- These limestones are referred by Mr. Gregory, though with some doubt, to
the Cretaceous series. (Quart. Journ. Geol. Soc. vol. xvii. 1861, p. 477.)
