II.—Post-Jurassic Earth-movements in South Africa

Extract

Mr. Bullen Newton has recently determined the fossils found by my students and myself in the Alexandria Beds near Port Elizabeth to be of Mio-Pliocene age; the full memoir will shortly be published in the Records of the Albany Museum, Grahamstown. Hitherto the Alexandria Beds have been regarded as Danian on the strength of the evidence afforded by the Polyzoa and casts of Lamellibranchs, but the well-preserved shells on which Mr. Newton founds his determination of the age of the beds leave no doubt but that this earlier one is wrong. If the beds had been Danian there should be some connexion between these and the Pondoland Cretaceous in regard to the conditions of their deposition, which there is not. In trying to clear the way for a better conception I endeavoured to show that as the affinities of the Pondoland fossils lay with Cenomanian forms from Tunis, the age of the Pondoland Beds was towards the lower half of the Upper Cretaceous; then the supposed Cretaceous beds of Alexandria with. Tertiary sharks’ teeth would represent transition beds between the Cretaceous and Eocene. Dr. Kitchin, however, objected to this, as the Pondoland fauna taken as a whole was Turonian, if not Senonian, and the gap between the Pondoland and the Alexandria Beds became so small that there was not time for the undoubted changes in the land to have taken place which would have allowed the deposition of these several formations in the positions we now find them.