Page:A sketch of the physical structure of Australia.djvu/33

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21

From other localities, whose precise geological or geographical place I do not know, the Rev. W. B. Clarke had, in addition to the above, collected the following fossils:

Favosites gothlandica.

One species of Crinoidea, apparently related to Platycrinus.
A form belonging to the radiata, and resembling an Echinoderma.
A small trilobite.
Two new sp. of Spirifer.

Two species of leptæna.

A terebratula.
An eurydesina.
An inoceramus.
A pleurotomaria.
A conularia.

Some persons have been struck with the oolitic aspect of the fossil plants collected in New South Wales (as also of those of India), and have been led to imagine, in consequence, that they did not belong to the same formation as that in which the productæ, spiriferæ, &c. above named, are found. All the physical characters and relations of the rocks, however, both in New South Wales and Tasmania, led me to look upon the whole series as one great continuous formation, and Mr. Clarke has since distinctly informed me, that he has obtained the same spiriferæ, productæ, &c. from beds above those which contain the fossil plants as are found in the beds below.

The perfect conformability and apparent passage from one group into the other would of itself render highly improbable any such difference of age between the higher and lower beds as exists between any palæozoic and any oolitic formation. As to the actual age of these beds, or their identification with any English or European formation, I should not be inclined to express any hasty opinion. Every one who sees the fossils, the long-winged Spiriferæ, the Productæ, and others, must of course be struck with their resemblance to those found in the Devonian formation of Europe. Even were the species identical, however, in rocks thus found at the two opposite sides of the globe, the strict synchronism of the two formations would not therefore be absolutely proved. Many questions, such as the original centre of production of the animals, and the time necessary for their migration and general spreading over the globe,—whether they might not have become