Page:Quarterly Journal of the Geological Society of London, vol. 26.djvu/346

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238 PROCEEDINGS OF THE GEOLOGICAL SOCIETY.


covered up; these are accompanied by Naticoe and Modioloe, which, though from the Upper Maranoa district, clearly connect them with the Wollumbilla fauna); and, thirdly, the large phragmacone 6 inches in length, in a matrix of dark-drab or olive limestone, from Wollumibilla, whence also are two small specimens which I succeeded in opening up in a very much water-worn block, with many Aviculoe &c.: these, Professor Phillips thinks, may possibly be young examples of the larger form, which he considers to approach B. paxillosus, a species ranging from the Middle Lias upwards. Regarding the other species, Professor Phillips remarks that they have stronger analogies with the Upper Oolitic forms than with any other. There is some analogy to the Speeton Belemnites, but scarcely any to the Neocomian species of the South of Europe. Professor Phillips's notes on the species will be given hereafter (see p. 258).

Vertebrata. — Numerous fragments of fish-teeth and scales, and a portion of a small vertebra, occur in the Wollumbilla blocks. They probably belong to Hybodus and Lepidotus. They are accompanied by some small, depressed, spine-like bodies, which Professor M'Coy supposed might be the hooks of Cephalopoda; but these are horny, whilst the former are enamelled, and they are, I have no doubt, of Ichthyic origin.

Resume. — For reasons already given, there seems to be no ground for doubting that all the organic remains from Western Australia and Queensland noticed in this paper have been obtained from blocks scattered through superficial deposits derived from the denudation of preexisting secondary deposits. That this denudation must have taken place over a great extent of the Australian continent is shown by the wide separation of the districts from which these remains have been collected.

It is very evident that all the Australian fossils which I have had under examination (except some plant- and insect-remains noticed in the following paper, see p. 261) are of true Mesozoic age, though the peculiar circumstances under which they are found necessarily render it very difficult to assign them to their precise geological horizons. Respecting the series from Shark's Bay, the Greenough Flats, and the Greenough River, Western Australia, from the presence among them of Ammonites and other fossils which are the typical species of certain horizons in this country, there seems to be no doubt that they have been derived from the equivalents of our Middle Lias, Upper Lias, and Inferior Oolite. Some of them, such as Ostrea Marshii and Lima proboscidea, pass up in England into the Fuller's-earth Oolite above; and it is remarkable that, though lithological conditions are not always a safe guide, in this instance the deposits also appear to be identical.

The same satisfactory conclusions, however, are not to be arrived at respecting the series from Queensland, the evidence as to the age of which I now proceed to consider.

The great majority of the Queensland fossils have been obtained from Wollumbilla, and come from the same geological formation. The blocks with the fine Pentacrinites australis, from the Amby