Page:The Natural History of Sokotra and Abd-el-Kuri.djvu/36

xxviii age, containing Gonistrata retiformis, is deposited in nearly horizontal strata up to about 40 feet above sea-level upon the archæan rocks west of the anchorage.



On the 5th December, soon after sunrise, we started for a long day on Gebel Saleh, the highest peak on the island. Proceeding northward along the strath over sand and shingle for al)Out two miles, we found a convenient spur on the north-west face leading more or less directly to the summit. From this aspect, which is entirely hidden from the anchorage, the mountain appeared quite clothed with dark green vegetation. Partly on the spur and partly in a neighbouring nullah we scrambled upward with much effort, seeking out our way over the roughest of ground. Huge blocks, themselves little hills in size, with perpendicular escarpments 50 to 60 feet in height dislodged from the limestone strata above, constantly barred our way and necessitated lengthened detours to circumvent them. Between the elevations of 500 and 600 feet, the vegetation, which below that had been