vi Transactions of the South African Philosophical Society. 



move a resolution in favour of the adoption of the same at the next 

 Meeting of the Society. 



A paper by Dr. E. Beoom on "The Structure and Affinities of the 

 Endothiodont Eeptiles " was read. Dr. Broom opposes the view 

 of Professor Seeley that Tritylodon was a Theriodont. His most 

 important argument is that the structure of the molars proves that 

 there was an anteroposterior motion for the mandible, and that 

 this movement would only be possible with the mammalian type 

 of articulation. 



Mr. A. L. du Toit read a paper on the " Forming of the 

 Drakensberg." 



The Drakensberg is the edge of a great elevated tract of country 

 built up of the sedimentary rocks of the Stormberg formation and 

 capped by a great thickness of volcanic material. 



The sediments were deposited in a great shallow lake, whose 

 shore-line stretched where the coast-ranges of the south of the 

 Colony now rise, extending eastwards into the Indian Ocean and 

 then north-eastwards parallel to the coast-line of Natal. This old 

 land surface was formed of quartzite of granite and metamorphic 

 rocks. 



The volcanic material was poured out from an immense number 

 of volcanic pipes and consist almost entirely of basic lavas with 

 occasional beds of volcanic ash, the flows being at first sub-aqueous 

 in character. 



At the close of the eruptions the area was affected by two sets of 

 gentle folds and intermittently elevated. Through depression in 

 the south-east the old land surface disappeared beneath the waters 

 of the Indian Ocean. 



By the action of rivers three marked plains of erosion were 

 produced at different altitudes, each marking a period of rest 

 followed by a period of elevation. 



The present escarpment of the Drakensberg which runs con- 

 tinuously for over 300 miles is due to the regular and rapid 

 erosion by the numerous streams flowing into the Indian Ocean. 



Ordinary Monthly Meeting. 



February 22, 1905. 



Dr. J. D. F. Gilchrist, President, in the Chair. 



Messrs. A. H. Wallis, District Engineer, C.G.E., was nominated 

 for election by A. Young and L. Peringuey ; A. Macco, Mining 

 Engineer, by E. Marloth and L. Peringuey ; W. E. Dewar, 



