Page:Quarterly Journal of the Geological Society of London, vol. 26.djvu/338

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of species. A single block of stone, about 10 inches by 6 inches, from the Oolite, shows that the deposit from which it was derived must have been very fossiliferous ; for within this space I have been able to detect as many as thirty species, belonging to the genera Ammonites, Belemnites, Trigonia, Pecten, Lima, Cuculloea, Avicula, Turbo, and other univalves, Rhynchonella, Teredo, Pentacrinus, &c. The shells are crowded upon one another in the greatest abundance, the bivalves being generally in single valves, showing that they were probably not deposited under tranquil conditions, or that they were not immediately covered up ; and the same may be inferred from the somewhat worn character of the fossils, which, in some instances, prevents their specific determination. With all the Australian Secondary deposits that have come under my notice much driftwood is found; and this, in some instances, has become mineralized and converted into iron-ore. The block of stone above mentioned contains the impression of a piece of wood which has since perished ; but a colony of Pholadidae, which had originally burrowed into it, still remained, about thirty of the shells, though in bad condition, being present. I propose for it the name of Teredo australis ; and it appears to be the oldest representative of the genus yet known.

On examining the series from Western Australia, not only is the similarity in lithological character of the beds with those in this country to be recognized, but the specific identity of many of their fossils cannot be doubted. I was especially gratified at recognizing amongst them such typical and well-known forms as Ammonites Moorei, Lycett (Pl. XV. fig. I), A. radians (Pl XV. fig. 2), A. Walcottii*, and Nautihis semistriatus of the Upper Lias, whilst A. Brocchii, Belemnites canaliculatus &c, represent organisms from the Inferior Oolite. Lima proboscidea and Ostrea Marshii appear to have been as abundant as in the hills around Bath ; and Pecten cinctus from Australia attains the same large proportions as in this country. The Cornbrash is apparently represented in Australia by Ammonites macrocephalus and Avicida echinata, and the Middle Lias by the Myacites liassianus before mentioned. It should be remarked that, as the Australian Oolitic species which are common to this country range from the Inferior Oolite to the Cornbrash, and as they are mostly found associated in the same rock in Australia, it is possible either that some of the species have a longer range, or that our separate divisions may not be there so clearly represented. Nothing is yet really known of the sections from which the fossils come.

It will be seen from the above, that the organic remains have enabled me to determine, for the first time, the presence in Australia of the faunas of the Middle and Upper Lias and the Lower Oolites ; and when I come to the Queensland fossils, equally satisfactory evidence will be adduced to show that the Upper Oolites are also represented on the Australian continent.

Out of the comparatively small number of specimens that have

  • Another locality in Western Australia, yielding Ammonites, is to the N.N.E.

of Wizard Peak, the Rev. W. B. Clarke having sent me photographs of A. radiant and A. macrocephalus from thence.