Page:Quarterly Journal of the Geological Society of London, vol. 26.djvu/343

From Wikisource
Jump to navigation Jump to search
This page needs to be proofread.

quently abraded, indicate that very beautiful examples of this genus may probably be obtained from that region.

On the surfaces of several of the blocks slight traces of carbonate of copper may be detected, as though they had been in contact with water holding that mineral in solution.

On comparing the general series of fossils, I at once saw that they had nothing in common with the Rhaetic beds or any of the Lower Secondary formations ; and on referring to the list given by Professor M'Coy of the species determined by him, this was the more apparent. The Myophorioe (nos. 23, 24, and 29) of his list, which unfortunately are not in good condition, and on the strength of which the presence of the Muschelkalk in Australia was affirmed, proved to be Trigonioe, very closely allied to the T. gibbosa of the Portland Oolite ; a slightly curved tubular shell, referred, but with some doubt, to Orthoceras, proved to be a small Serpula ; nor were any of the species identical, as suggested by Professor M'Coy, with any belonging to the Triassic or Liassic series. Amongst the specimens was a part of a so-called "Ammonite " (from the Upper Maranoa) ; but this I recognized as a portion of the inner whorls of a gigantic Crioceras. Another block contained five lobes of the terminal chambers of probably the same specimen, which portion alone measured 14 inches in length ; so that the shell must have attained a size exceeding that of any which lived at the Neocomian period.

These and other circumstances indicated a higher horizon for the Queensland fossils ; and I now proceed to give those of most importance a more detailed consideration, after which I shall endeavour, as well as the difficulties they present will permit, to refer them to their probable geological positions.

Organic Remains from Queensland.

Amorphozoa. — This order is represented amongst the Queensland specimens by a large siliceo-fibrous Sponge, closely allied to Dactylocalyx, Stutchb. I have been favoured with a description of it by Dr. Bowerbank, who proposes for it the new genus Purisiphonia, and names it P. Clarkei, after the Rev. W. B. Clarke, F.G.S., through whose exertions, aided by zealous friends in the interior, the collection of fossils now under notice has been brought together. The specimen has been decalcified by Dr. Bowerbank by means of hydrochloric acid, the skeleton-tissue being in a very beautiful state of preservation.

This form appears not to have been uncommon, as numerous fragments may be detected projecting from the surfaces of some of the blocks from Wollumbilla. It is stated by Dr. Bowerbank that this Sponge has affinities with a group which hitherto has not been found in England lower than the Chalk of Flamborough Head, and that he considers the matrix containing the Sponge to be of a similar character to the hard Chalk of that district. Only the above species is present in the Australian collection. Dr. Bowerbanks notes on the genus are appended hereto (see p. 240).

Foraminifera. — Of this group five genera are represented, the