1865.] KTJBIDGE— SOUTH AFEICA. 439 



interval of country left doubtful between the Devonian (" Upper 

 Silurian ") and the " Carboniferous " by Mr. Bain may, by the dis- 

 covery of fossils at "Wniowmore and Antoniesberg, be safely referred 

 to the same formation. 



3. It follows that, having proved the clay- slate to be Devonian, 

 the sandstone which rests unconformably on it must be something 

 considerably newer ; and I had a suspicion that it might represent 

 altered conditions of the great lake-formation of the interior, in 

 which the Bicynodon and his numerous congeners lie fossilized. 

 Mr. Salter tells me that a Calamite which was found at Riquet- 

 berg, and kindly sent to me by Mr. Layard, proves the Table-Moun- 

 tain sandstones, in which it occurred, to be not older than the 

 Carboniferous epoch. It is very much like some of the same genus 

 that I found near the Orange River in the Dicynodon-rocks. 



4. I did not see any reason for placing any rocks between the 

 Devonian and the DicjTiodon-rocks. I have found the same kind of 

 stems as those which occur in the Devonian rocks near Salem, at 

 Wolve Kraal and at Pickel Vontein, in Ecca Pass, and at the Yander 

 Merwes River, in inclined rocks not far from the almost horizontal 

 Dicynodon- strata, which appeared to be unconformable to them. I 

 am not, however, quite so certain of this correction as of the others. 

 I am safe, I think, in sajdng that the evidence for any intermediate 

 strata is not satisfactory. 



By making the corrections here pointed out as necessary, it will 

 be seen that, in the Map published by the Society ten years ago, only 

 that portion of the Palaeozoic rocks coloured " Upper Silurian " 

 (siuce called " Devonian," on the authority of Messrs. Sharpe and 

 Salter) rests where it did. I laid before the British Association at 

 Bath the evidence, in a condensed form, on which these changes are 

 made, in hope that the proof of work done would draw the attention 

 of geologists to a matter which I conceive to be of infinitely more 

 interest, — namely, the principle which led me to predict so many 

 years ago the changes I have since made. I will not go into the 

 evidence of this principle ; it maj^ be found elsewhere by those who 

 would seek it*. Suffice to say here, that the quartzose sandstones, of 

 which the Zeurbergen and other great ranges are formed, are regarded 

 by all geologists who have examined them as interstratified with 

 the Devonian rocks, which they cross at such angles that a section 

 of ten miles across the strike may be all schists at one place, and at 

 another ten miles distant all quartzites. 



Mat 24, 1865. 



James Philip Baker, Esq., "Wolverhampton ; George William Clive, 

 Esq., 38 Albemarle Street, Piccadilly ; James Coutts Crawford, Esq., 

 Wellington, New Zealand; Theodore H. Hughes, Esq., of the ( eo- 

 logical Survey of India; and Charles Ottley Groom iSapier, Esq., of 

 Bristol, were elected EeUows. 



* See ' Geologist,' vol. v. p. Ii7, &c.. and p. 3G6, &c. 



