Page:Quarterly Journal of the Geological Society of London, vol. 27.djvu/696

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opposite side of the same basin — namely, from the Upper Zwart Kei, north of the Winterberg, and 60 or 70 miles S.S.W. of Dordrecht. The sketch map (fig. 10) is to explain how the sides of this range of hills are worn away, rising from the more level ground to the top of the ridge. In the section the outlines of the Great Winterberg and the Groot Tafelberg are shown in the distance, to mark the relative positions in which they are seen from this point.

On the top of this ridge is found at 14, 14, a mass of enormous blocks of disintegrated basalt capping its edge. Similar blocks are found at a lower portion of the ridge resting on No. 9. No. 13 is a very hard compact sandstone, weathered into vertical lines until it has assumed an almost columnar or basaltic appearance ; but on being broken, it displays distinct lines of horizontal stratification. It forms a precipice some 30 feet high along the face of the hills. Below this is a coarse-grained sandstone (No. 11, 11), sloping away to the bed of shale (No. 10) immediately underlying it. This shale is upwards of 200 feet thick, and of a much darker colour than the shales below ; no fossils have yet been found in it. It forms a sloping shoulder all along the hills, as shown on the left of the section; and its position in the map is at 10, 10, 10. It rests upon a coarse-grained sandstone (No. 9), the exact thickness of which is unknown. This covers a sandy shale (15), about eight feet in its thickest part, and gradually thinning out. In this shale (15) Mr. Donald White discovered the fragment of bone D. S. 39*, and the fossil D. S. 40*. Below this is a shale (7, 7, 7), varying in thickness, and about 20 feet where thickest, interlaminated with thin streaks of bluish clay, and near the top discoloured with innumerable specks of carbonized matter. No. 6 is a gritty greyish sandstone (specimen D. S. 45*), about 200 feet thick. This becomes exceedingly coarse- grained in the uppermost beds. In its lower portion were found the reptilian skull (D. S. 35*) and the fragments of bone (D. S. 36 and 37*) ; at the spot marked " 5 " the lowest band is quite a plant-bed, of which D. S. 38 and D. S. 43 and 44 are specimens *.

No. 4, beneath this, is a concretionary sandstone (see specimen D. S. 46*), containing fragments of shale and quartz, together with nodules, such as those sent† (Nos. D. S. 29 to D. S. 34). Three beds of similar rock occur in the outlier b. At one spot, as in stratum 3, it appears as if the shale had been cut through by some stream or current down to the sandstone beneath, and the nodular sandstone (4) deposited in the space thus denuded. If this supposition be correct, the banks of this ancient stream must have been at

  • D. S. 35. Small skull in sandstone, with calcareous cement. 36. Bone in

similar sandstone. 37. Bone in concretionary calcareous sandstone. 38. Fine- grained concretionary calcareous sandstone as above, with Calamites (?). 39. Sandstone, with calcareous cement, containing bone. 40. Tooth in calcareous sandstone, as 39 ; the other part of the specimen is greenstone. 43 and 44. Pine-grained sandstone, with highly calcareous cement, and containing Pecopteris(?). 45. Fine-grained sandstone. 46. Concretionary, fine-grained, calcareous sandstone, with some films of shale. — T. R. J.

† Sandy, chatoyant, radiating calcite. — T. R. J.