﻿366 MR. FEKDERIC P. MENNELL ON THE [Aug. I9IO, 



For the most part, therefore, we can, in discussing the relations 

 of the beds, only rely on lithological considerations and the very- 

 scanty stratigraphical evidence, and we can scarcely adopt a de- 

 tailed classification of them until after much more extended field 

 observations than have so far been made. Mr. Lamplugh has 

 already suggested 1 that the ' Sijarira Series ' may be only the Mato- 

 bola Beds in the vicinity of the fault which forms the boundary of 

 the Victoria Falls basalts. This may be the case, but I think it 

 more probable that the beds are Forest Sandstones overlapping the 

 coal-beds in the north, as it is well recognized they do in the south, 

 and with their relations complicated by faulting. This is strongly 

 suggested by Mr. Molyneux's own description, 2 and such an overlap 

 was actually recorded by the late Mr. C. E. Parsons, F.G.S., 3 east 

 of this area. Moreover, so far as the Limpopo basin is concerned, 

 Mr. Molyneux has himself recently included the ' Samkoto Series ' 

 with the Forest Sandstones, 1 which renders it unnecessary here to 

 do more than recall the fact. With regard to the ' Thaba-s'Induna 

 Series,' it had already been pointed out by me that the white beds 

 exposed at Taba-s'Induna are evidently the same as those seen 

 underlying the red flaggy beds of what was subsequently termed 

 the ' Forest Sandstone Series ' at Pasipas Hill, about 12 miles 

 north of Bulawayo. So far as I have been able to judge from an 

 examination of the ground near the Ifafe River, and from Mr. Par- 

 sons's more extensive observations farther north, there also appear 

 to be no good grounds for separating the ' Escarpment Grits ' from 

 the Forest Sandstones. Apart from a slight anticline cut into by the 

 lfafe itself, the beds have a gentle northerly dip : and, as the ground 

 rises considerably for a good many miles, higher and higher beds 

 come on, until we reach the red sandstones and basaltic sheet of 

 Sikonyaula's, which caps the edge of the drop where the grits are 

 developed. If, therefore, we regard these last as a separate 

 formation, nothing remains of the Forest Sandstone Series. The 

 Matobola and Busse Beds may be provisionally accepted as local 

 subdivisions of the Sengwe coal-series; but, as they cannot be recog- 

 nized at Wankies, the best-known and most important coalfield, 

 and, moreover, the only one accessible under present conditions, it 

 seems best not to attempt any general classification of the Coal 

 Series until further evidence is available. The ' Boomka Flags ' of 

 Mr. Lamplugh are evidently the fine greenish tufaceous sandstones 

 interbedded with the basalts at several localities, as, for example, 

 near the Deka River, and near Sawmills siding, and may therefore 

 be referred, as he evidently suspected, to the upper part of the 

 Forest Sandstone Series. 



As regards other formations, it was, I believe, first noticed by 

 Mr. Parsons, 6 that in several borings for coal in the Mafungabusi 



1 Quart. Journ. G-eol. Soc. vol. lxiii (1907) p. 181. 



2 Ibid. vol. lix(1903)p. 271. 



3 Proc. Ehod. Sci. Assoc, vol. iv (1904) p. 51. 



4 Eep. S.A. Assoc. Adv. Sci. for 1908, p. 108. 



8 1st Ann. Eep. Ehod. Mue. for 1902 (1903) p. 9. 

 6 Proc. Ehod. Sci. Assoc, vol. iv (1904) p. .50 & pi. v. 



