Mr. R. Pinchin on the Geologg of the Cape of Good Hope. 229 



Q. J. G. S. vol. xxix. p. 417), the author stated that in a pit near Ash- 

 well the " Lower Chalk without flints " exhibits a bed of a concre- 

 tionary nature, the concretions in which are marked nearly all over 

 with lines. The lines are found only on the concretions and in their 

 immediate neighbourhood. The fossils in the bed are invariably 

 crushed, as if by pressure. The author believes that the striae are 

 due to an incipient crystallization arising from the formation of the 

 concretions ; and in support of this view he adduced a specimen of 

 iron pyrites from the chalk of Beachy Head, attached to which is a 

 small portion of very hard striated chalk, and suggested that the 

 crystallization of the pyrites had induced a crystallization in the chalk. 

 He considers, however, that in some places an almost identical 

 structure may be due to slickensides, but only in very broken and 

 faulted beds. 



2. "A short description of the Geology of the Eastern Province 

 of the' Colony of the Cape of Good Hope." By R. Pinchin, Esq., 

 C.E. Communicated by H. W. Bristow, Esq., F.R.S., E.G.S. 



In this paper, which was illustrated by maps and sections, the 

 author gave the results of his observations on the geology of the 

 above region. The two principal sections described were from Cape 

 Saint Erancis, across the Great Winterhoek and Langeberg ranges, to 

 the lacustrine Triassic rocks near Jansenville, and from Port Eliza- 

 beth to Somerset. The lowest rock in the first section is the quartzite 

 of the Great Winterhoek, which is immediately overlain to the 

 northward by clay-shales and sandstones containing Devonian fossils. 

 Beds with similar fossils occur at the Kromrae river, Cape St. 

 Erancis, and near Uitenhage. A patch of horizontal secondary 

 strata stretches west from the Gamtoos river, overlying the Enon 

 conglomerate in the same way as the Jurassic strata of Uitenhage. 

 They contain no fossils. The Enon conglomerate is seen on the 

 flanks of the higher hills. The northern ranges, Langeberg, Klein 

 Winterhoek, and Zuurbergen, are regarded by the author as formed 

 of rocks belonging to the Carboniferous series, although closely 

 resembling those of the Great Winterhoek in lithological character, 

 except that among them are bands of the peculiar rock described by 

 Bain as " Claystone porphyry," by Wyley asa u Trap conglomerate/' 

 by Tate as a " Trap-breccia," and by Atherstone as an " intrusive 

 Trap." Rubidge regarded it as a metamorphic rock ; and this view 

 is adopted by the author, who describes it as underlying and over- 

 lying the clay-shales, which always separate it from the quartzite, 

 and as passing imperceptibly into the clay-shales. The mottled 

 sandstone or Ecca rock is referred by the author to the Carboni- 

 ferous series. The author also noticed the occurrence of Tertiary 

 or recent rocks containing remains of Mollusca identical with 

 species now living in the adjacent seas, lying unconformably upon 

 the Devonian, and conformably upon the Secondary rocks at various 

 places near the coast. 



