THE CRETACEOUS SYSTEM 307 



At a spot about three miles east of the village of 

 Herbertsdale there are some shales containing plant 

 remains. Four species have been recognised amongst 

 them, Cladophlebis denticulata forma atherstonei, which 

 also occurs at Dunbrody in the Wood beds, Taeniopteris, 

 also found at Dunbrody, Osmundites kolbei and Taxites. 

 The shales are very soft and easily weathered, so that 

 the exposures are few. The Herbertsdale outcrop 

 has been opened up for prospecting purposes owing to 

 the presence of small fragments of black lignite, which 

 led to the expectation of a workable deposit of coal. No 

 such reward met the searchers, but their work furnished 

 the means of obtaining the four species of plants 

 mentioned above. In a fairly well- watered country like 

 the Mossel Bay Division soft shales are usually covered 

 up by soil and vegetation, and in the absence of quarries, 

 pits and cuttings, it is extremely difficult to get out 

 any fossils there may be in the rock. Although the 

 Herbertsdale plants are almost the only ones yet found 

 west of the Uitenhage district there must be many more 

 awaiting discovery, and any further specimens will be 

 of very great interest. 



Many casts of parts of stems have been found in the 

 hard sandstone of Cape St. Blaize, but hitherto none 

 of them have been determined. 



The underlying surface of the Cape formation and 

 Pre-Cape rocks is probably very uneven. In the Lang 

 Touw Valley below Herbertsdale some sections are ex- 

 posed showing the conglomerates and sands of the 

 Uitenhage beds resting against a steep almost cliff-like 



face of Bokkeveld beds, the north slope of an old valley 



20* 



