Page:Quarterly Journal of the Geological Society of London, vol. 25.djvu/113

 Discussion.

Mr. Gwyn Jeffreys corroborated the opinion of the author, that there had been at one time permanent marshy lands where he found Lymnoea truncatula and a species of Pisidium.

Mr. D. Forbes inquired the age of the schists and porphyries of Om Riglaine, and as to the character of the granite.

Sir R. I. Murchison inquired the probable age of the masses of gypseous rocks, and commented on the extremely wide range of the Nummulitic strata.

Dr. Duncan remarked that the Cretaceous fossils, as had been observed by both M. Louis Lartet and himself, belonged to the Upper Greensand formation. He considered that the author had proved that the Red Sandstone was not, as suggested by M. L. Lartet, Neocomian, but either Triassic or Permian. Fossils of the Upper Chalk with flints he found to be absent. He had found that, out of 25 Cretaceous species, 13 had been described by M. Coquand from Kabylia and Egypt, while 8 were European forms.

Mr. Etheridge considered the fossils from the sandstone to belong to the Trias, especially from the presence of Encrinus moniliformis.

Prof. T. RUPERT JONES regarded the Nummulites as of the common typical form found in Egypt — the Nummulina Ghyzensis, with N. Ramondi and varieties. If the Nummulitic rocks were overlain by the soft white friable limestone, this latter, like similar beds in Scinde, would be of later date, though similar in lithological character to a bed spoken of as being underneath.

Mr. W. W. Smyth had found in Nubia, above the Catacombs, red sandstones overlain by limestone and Nummulitic beds. If the Red Sandstone, as seems probable from the fossils discovered by Mr. Bauerman, were proved to be Trias, a great point in the geology of Sinai and of the East had been gained.

Mr. Boyd Dawkins inquired as to the evidence of the mines having been worked by the Egyptians.

Mr. Evans was not satisfied that the flint flakes had been used in the manner suggested, as they would be liable to break off in the socket, and the hammers would not be worn away in the manner they exhibited by mere impact on wood.

Mr. Carruthers remarked that the fragment of wood exhibited had not been used as a wedge, as the fibres were not in any way disturbed, as they would have been by the impact of a hammer. He believed that it was broken from a much worn mallet made of coniferous wood.

The President commented on the similarity of the faunas of India and South Africa, and hoped that Mr. Bauerman's future researches might throw light on the ancient connexion of these continents.

Mr. Bauerman stated in reply that he did not regard the white limestone as true chalk. He considered that the slabs showed conclusive evidence of having been chiselled by means of the flints.