Mr. Bain on the Geology of Southern Africa. 185 



and various other Mollusks, giving the formation, on the whole, perhaps more of 



an oolitic than a liassic character*. 



Resting unconformably on the lias (?) and the older rocks along the coast, are 



several 



Tertiary Formations, 



principally of white calcareous rock, which I shall not attempt to describe, as I 

 can neither correctly lay down their boundaries, nor has my experience among 

 them qualified me to enter into particulars. They are probably of the Phocene 

 age, as they contain many specimens of Mollusks at present inhabiting the neigh- 

 bouring seas. My collection contains a few specimens, principally from the eastern 

 province, and one from Mossel Bay. 



Having now briefly described the rock-formations in the more southerly portions 

 of the Sections Nos. 1 and 2, I shall pass over that part of No. 3 (Plate XXI.) 

 which contains what has been already described until we reach the 



Clay stone Porphyry, 



a description of which I attempted in my paper before referred to {supra, p. 54), as 

 far as I then knew it to extend, viz. from the mouth of the Gualana River in Kafir- 

 land to the Little Fish River in the Division of Somerset, a distance of eighty miles. 

 I little dreamt then of its enormous extent, or to what important conclusions it 

 would lead, fori have since traced it (with the exception of a small tract of country 

 which I have had no opportunity of exploring, but through which I have no 

 doubt it is continuous all the way, as above described) from the Gualana Mouth, 

 behind the Zuurbergen and further along, and running nearly parallel to the Great 

 Swartberg, Witteberg, and Cedarberg ranges, up to where my researches termi- 

 nate, in a north-west direction as far as Hantam in the Clan William Division ; a 

 distance of nearly 600 miles. How much farther it may extend is a problem for 

 future geologists to solve. 



This enormous igneous mass, as will be seen by the map and sections, rests on 

 the carboniferous rocks in the eastern province, and in the western parts on the 

 flanks of our Upper Silurian (?) ranges, running, like the mountain chains, generally 



* In 1851 Col. Portlock exhibited to the Meeting of the British Association at Ipswich a series of 

 fossils collected by Mr. R. Rubidge at Sunday River ; and observed that they comprised Ammonites, 

 Gryphea, Pholadomya, and Trigonia ; together with plants of the genera Zamia, Neuropteris, Pecopteris, 

 and Sphenopteris . " The shells were apparently of Jurassic age ; the plants had been examined by 

 Dr. Harvey, and the species of Neuropteris, Pecopteris, and Sphenopteris were regarded as chiefly re- 

 sembling those of the coal of Australia ; whilst the presence of the genus Zamia in abundance impresses 

 an oolitic aspect on the flora." Report Brit. Assoc. 1851, Sect. p. 68. [From a late communication from 

 Mr. Rubidge, it appears doubtful whether some of the plants here alluded to were not derived from the 

 Karoo series on the eastern side of the Stormberg.] — Ed. 



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