442 Annals of tlte S'jutJi African Museum. 



pebbly felspatliic sandstone separated by bluish and grey softer 

 weathering, line-grained sandstones, mudstone, and shale. The sand- 

 stone contains a good deal of felspar, fragments of which are frequently 

 '/4 in. in diameter, while the grains of quartz frequently exhibit partial 

 restoration of the crystal faces, giving rise to "glittering sandstones". 

 Small pebbles of vein-quartz are abundant in certain layers. Sporadic 

 pebbles of granite, graphic granite, and white line-grained quartzite 

 occur, more commonly near the base of the series and frequently 

 just above, or even resting on, a coal seam. 



The Indwe Sandstone and Gubenxa sandstone are well represented. 

 The top of the series here is a more than usually coarse pebbly sandstone. 



Griqualand East. Du Toit has described the Molteno Beds in this 

 area from the Divisions of Maclear, Mount Fletcher, Qumbu, and 

 Mount Frere. The beds bear a close relation to those in the Transkei. 

 In no place are they more than 1800 feet thick and are essentially 

 arenaceous. Iron pyrites is found in irregular layers in the sand- 

 stones in a few localities. 



Du Toit describes the beds as having the following characteristics. 

 "The sandstones contain a good deal of felspar, usually rather de- 

 composed. The pieces of felspar may, in cases, attain a diameter of 

 half an inch, while in a railway cutting, about a mile south of Ugie 

 Station, small pebbles of granite and graphic granite were observed 

 in addition. The grains of quartz frequently show partial restoration 

 of the crystal faces, and the light reflected from these facets gives 

 the rock a sparkling appearance in the sunlight ; hence the appropriate 

 name of "glittering sandstone" given to them. Small pebbles of white 

 or blue-black quartz up to an inch or thereabout in length are most 

 characteristic of these sandstones, and some portions are so pebbly 

 in character that they can almost be termed conglomerates." 



Further to the north-east, in Mount Currie on the Natal Border, 

 the thickness has diminished to about 1100 feet, even to 950 feet 

 just over the border. The layers of coarse pebbly sandstone are thinner 

 and spaced closer together than in Maclear. "Otherwise the formation 

 is the same, e.g coarse-grained pebbly sandstones and grits usually 

 false-bedded and sometimes conglomeratic and crowded with smooth 

 water-worn quartz pebbles - - rather fe) spathic and passing into grey 

 liner-grained types: most of the sandstone sparkles or "glitters" in 

 sunlight owing to the reflection of light from the faces of quartz 

 crystals". The pebbles in the Indwe Sandstone range from a few 

 inches up to a foot in length. At one place there is a ferruginous 

 conglomerate full of quartzite pebbles. Below the Indwe Sandstone 



