228 Reviews — Geological Report of Cape of Good Hope. 



false-bedded and ripple-marked, show worm-casts and definite 

 animal trails. This Ibiquas series (named after a local tribe ot* 

 natives) extends from the north-eastern part of Van Ehyn's Dorp 

 district into Calvinia ; it appears to be much thicker than the 

 Bokkeveld series, which in places is seen to be unconformable 

 above it. 



In this survey we have also an account of the local range of 

 the Table Mountain Sandstone, the Bokkeveld Beds, the Dwyka 

 series, and its continuation to Prieska and Hope Town. The 

 peculiar White Band, lying on the Dwyka Conglomerate, owes its 

 appearance to the slow combustion of a carbonaceous shale under 

 atmospheric agencies. The thick shales and sandstones of the 

 Ecca series, above the White Band, contain some ferns and calamites 

 in the south. The local dykes and sheets of Dolerite are described 

 in detail. They all belong to one series of intrusions ; and, like 

 the Karoo dolerite type, consist of a moderately coarse plagioclase- 

 augite-olivine rock. 



III. The survey from Beaufort West to Calvinia (pp. 55 to 64:) 

 showed mostly horizontal beds of the Karoo series of shales and 

 sandstones, pierced vertically and horizontally with dykes and 

 sheets of the usual dolerite. The shape and constitution of the 

 hills very much depend on the presence of this intrusive rock and 

 the peculiar modes of its weathering. A remarkable cylindrical 

 hole, near Eatel Fontein, in sandstone and shale, is filled with rocks 

 and minerals such as are found elsewhere associated with diamonds,^ 

 but they are absent here. 



IV. (Pages 65 to 79.) The geology of the Cedarbergen and 

 adjoining country between the Gydr Pass on the south and the 

 Pakhuis Pass on the north comprises the Table Mountain Sand- 

 stone, the Bokkeveld, and the Witteberg series. In the Table 

 Mountain Sandstone (Lower Devonian) of the Pakhuis Pass there 

 is undoubted evidence of local glacial action contemporaneous with 

 the deposition of the sandstone and shale or mudstone, with glaciated 

 pebbles in early Devonian times. 



In a separate paper on this Glacial Conglomerate in the Table 

 Mountain Sandstone read before the South African Philosophical 

 Society in February, 1901, Mr. A. W. Rogers gave further par- 

 ticulars as to the character and condition of this deposit, illustrated 

 by a plan and section (Trans. S.A. Phil. Soc, vol. xi, pt. 4, 

 pp. 236-242). He states that "The shale band was first recognised 

 by Mr. Schwarz in the Hex River and Warm Bokkeveld Mountains. 

 In the 1st Ann. Rep. Geol. Comm. C.G.H. for 1896, p. 27, he 

 describes two shale bands, one near the Table Mountain Sandstone 

 and the other near the bottom : the upper of these two is the one 

 referred to above. The course of this band between the Schurfte- 

 bergen and Pakhuis is described in the 5th Ann. Rep. for 1900." 



The results of 1900 were obtained under very disadvantageous 

 circumstances owing to the War, but they have been welcome 

 additions to geological knowledge : (1) especially as to the relationship 

 of the Ecca series and the associated so-called Dwyka Conglomerate 



