Page:Quarterly Journal of the Geological Society of London, vol. 27.djvu/150

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To the Secretary of the Geological Society.

Yorktown, January 28, 1871.

Dear Sir, — Subsequent to the reading of Dr. Grey's " Notes on some Fossils from South Africa," it occurred to me that it is highly probable that the upper or " Stormberg " division only of the " Karoo formation " reaches so far north as the Orange-River Free State, the middle and lower divisions never having been deposited in that region. In this case, the Stormberg strata (of Secondary age) containing the coal with Paloeozamioe (Atherstone and Stow) have overlapped the Lower Karoo beds, and have been deposited directly on palaeozoic rocks continuous with those of the Transvaal. These old rocks might well be of Carboniferous age, with old coal ; for the Devonian rocks appear to the north in the Transvaal ; and in Natal the Karoo beds are said by Mr. Griesbach to occur in proximity to the Carboniferous rocks, but unconformably and separated by igneous intrusions. In the Stormberg, therefore, it is possible that the Karoo coal-beds may be resting on the old Carboniferous rocks ; and these latter may have yielded the really old coal-plants that have been sent by Dr. Grey from the Stormberg section, and which were also referred to by the late Dr. Rubidge some years ago.

Yours, &c,

T. Rupert Jones.

2. On some points in South -African Geology. — Part II. By G. W. Stow, Esq.

(Communicated by Prof. T. Rupert Jones, F.G.S.)

[Abstract*.]

This paper commenced with a detailed account of the Forest zones, coal, and other strata of the Karoo formation, as seen in sections in the Winterberg and Stormberg. The author particularly pointed out the position of the Fern-beds at Dordrecht, of the Reptilian remains found on the Upper Zwartkei, and of the Coal on the Klaas Smits River. He next referred to the climatal changes of South Africa, as indicated by its geology and fossils, particularly the Karoo beds, the Enon-conglomerate, the Trigonia -beds, the several post-Tertiary shell-beds, and especially the present surface conditions, which he regarded as due to ice-action, as evidence of which he adduces roches moutonnees, moraines, basins, and striae, both north and south of the Stormberg, in British Kaffraria, and even in Lower Albany. He concluded with remarks on the probable succession of periods, and on the former existence of a great southern continent.

Discussion.

Prof. Ramsay expressed a hope that the author at some future time would discuss the numerous subjects of which he treated at

  • The publication of this paper is deferred.