190 Mr. Bain on the Geology of Southern Africa. 



In my former communication of 1844, so frequently alluded to, I offered some 

 conjectures as to the probable age of the Reptiliferous strata, being in a great mea- 

 sure misled in the opinion then offered by having received an Ammonites planulatus, 

 said to have been found in situ by the donor at the foot of the Spitzkop ; circum- 

 stances which I need not here relate, coupled with a subsequent better acquaint- 

 ance of that elevated part of the country, led to the discovery that this was quite a 

 mistake, — the fossil having been brought from Europe. Professor Owen appears 

 to consider the Bidental Reptiles to be of the age of the New Red Sandstone ; 

 and, from extensive researches made among the Reptiliferous strata since the 

 transmission of my first collection to England, at which time I erroneously 

 assigned to them an Oolitic origin, I now perfectly concur with the learned Pro- 

 fessor, that they are at least as old as, if not older than the New Red period. 



I have in my possession a fine specimen of the heterocercal tail of a fish, 

 found at Styl Krantz in the upper Reptiliferous slates ; and I have seen various 

 other ichthyohtes of a similar description, found near Fort Beaufort in the lowest 

 part of the same formation ; — and perhaps, from the presumed palaeozoic character 

 of such fish-remains, we may find another argument in favour of the inference that 

 these beds are at least as old as the New Red Sandstone. 



But I am inclined to assign to them even an older date. Although I have 

 classed my " Carboniferous formation" among the marine formations, yet I am by 

 no means certain that they are such, for no marine exuviae, as far as I am aware, 

 have ever been discovered in them. Lithologically they differ much from the 

 Carboniferous series of Europe, but I think they are their true African equivalents ; 

 and the great resemblance between their fossil flora and that of my " lacustrine " 

 deposits which contain such extensive beds of coal, even in their upper parts, 

 irresistibly lead me to the conclusion that they are also nearly related to the 

 Carboniferous series, and hence that the Dicynodon, with its numerous and 

 wonderful congeners, are amongst the oldest of reptiles. 



Before concluding, I shall offer a few general remarks on the Superficial deposits 

 of South Africa. 



Very extensive deposits of calcareous Tufa are found along the coast (see 

 Section No. 4) ; these are composed principally of the detritus of the Tertiary 

 formations, which I have no doubt at a former period everywhere fringed the 



shells, some of which may have been estuarine (see PI. XXVIII. figs. 8-25), was said doubtfully to 

 have come from Snieuwberg, but it is a part of the lowest Zwartkop rock. Another rock with casts 

 of minute (Cyclas-Uke) shells is unfortunately without a label, and may correspond to some specimens from 

 Kat River referred to in Mr. Bain's MS. Catalogue : if so, it might have aided the author's arguments. 

 The freshwater fossils from near Graaf Reinet (PI. XXVIII. figs. 2-7), in the Society's collection, 

 constitute at present all the direct evidence we have on this point. — Ed, 



