Page:Quarterly Journal of the Geological Society of London, vol. 28.djvu/346

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marine beds are seen to rest directly on a coal-seam was at Pelican Creek, a tributary of the Bowen river, a view of which is here given (Fig. 10). At the base of this cliff a seam of coal about four feet thick crops out the entire length of the section. Directly upon this rests a coarse-grained sandstone, with a few imperfect casts of shells, while at the top of the cliff an arenaceous limestone band holds abundant specimens of the Streptorhynchus crenistria, so common throughout all the lower marine series.

No plant-remains could be detected in the section ; but (as will be observed in the view) the dip is very slight down the creek; and in the next cliff, on the downward course of the stream, we have a section of the measures of nearly the same dimensions, with shale and sandstone interstratified, in which very perfect impressions of Glossopteris were found.

In fact, throughout Australia, as far as observation has yet extended, Glossopteris is confined to the older coal-measures, of which the Producti and Spiriferoe above described are the marine representatives. In Tasmania, New South Wales, and Queensland, at least, this holds good ; and where Glossopteris occurs, the associated marine fauna is always of Palaeozoic type.

In the Taeniopteris coal-measures of Victoria, Richmond River, New South Wales, and the Southern coal-field of Queensland no Glossopteris has yet been found, and the Productus- and Spirifera-beds are also absent. It would seem therefore that, apart from the presence of a distinguishing fauna, Toeniopteris may be taken as evidence of the Mesozoic, and Glossopteris of the Palaeozoic coal-formations of Australia.

Devonian. — From the southern boundary of Queensland up to latitude 18° south, a series of slates, sandstones, coral-limestones, and conglomerates extend to a distance of 200 miles inland ; these are sometimes overlain by coal-measures, sometimes by volcanic rocks, and consequently do not crop out on the surface over such districts. Their average dip and general character are shown in Fig. 11.

Isolated granitic and metamorphic areas also occur in the same belt of country ; these either were islands in the ocean whose accumulated sediments they represent, or have been laid bare by subsequent denudation or intrusion.

North of latitude 18° south, however, over the Cape York Peninsula, this series (so far as we have any evidence) is absent, granites and porphyries capped by " Desert Sandstone " forming the ranges on the eastern, and their abraded ingredients, the sandy tea-tree flats, those on the western side of that inhospitable tract of country.

Lithologically this very extensive development of Palaeozoic rocks agrees with the " Devonian " system of England ; and the palaeontological evidence is confirmatory of the same idea. In the higher members of this group, which, from their general analogy to the English group of that name, we will term Devonian, specimens of fossil plants are abundantly met with.

W. Carruthers, Esq., F.R.S., has described and named those from