=Gebel Derhib=, 1,160 metres above the sea, is a mountain separating Wadi Abu Gurdi from Wadi Egat; it is really an extension of Gebel Abu Gurdi, from the beacon on which its summit is six and a half kilometres west. =Gebel Um Goradi= is likewise in reality part of the Abu Gurdi mass, forming the end of a spur extending south-eastward for ten kilometres from the main peak. The Wadi Lahami curves round its foot northward, passing between it and Gebel Um Gunud. =Gebel Selaia=[107] (the bald head) is a very remarkable rounded granite boss rising from the plain thirty-one kilometres south-south-west of Gebel Hamata. Owing to its peculiar shape, isolated position, and considerable height (its top is 787 metres above sea-level and about 260 metres above the plain), Selaia is a conspicuous landmark for great distances round it. The lower illustration on Plate XI (p. 172) gives an idea of its appearance as seen from the east; from the north or south it appears much steeper. South-east of Gebel Selaia stretches a line of four smaller granite hills. The first of these, about a kilometre from the great boss, is interesting as having a small spring, called Megal el Selaia, at its foot. The next, one and a half kilometres further on, is larger, while the third is larger still, rising to 623 metres above sea-level. The fourth, five kilometres from Gebel Selaia, is marked by a triangulation beacon, 563 metres above sea-level and about fifty metres above the plain, in latitude 23° 55′ 30″, longitude 34° 54′ 37″. =Gebel el Homur= is an isolated mass of granite hills on the plain six kilometres north-east of Selaia. Its highest point is 731 metres above sea and 230 metres above the plain at its foot. It is drained by small feeders of the Wadi Abu Gurdi, which passes north of the mass on its way across the plain to join Wadi Kharit. =Gebel Abu Derega= is an isolated mass of higher granite hills thirteen kilometres south-east of Gebel Selaia. Its highest point is 831 metres above sea-level, and about 300 metres above the plain. Gebel Abu Derega is on the Nile — Red Sea watershed, which crosses the plain from east to west in this locality. The northern drainage is to the Wadi Elemikan, which runs between Gebels Abu Derega and Selaia to join Wadi Kharit, while the southern faces of the hills are drained by feeders of the Wadi el Khiua, a tributary of Wadi Um Bisilla, in the basin of Wadi Hodein.