PHYSICAL FEATUEES. xxvii 
mountains by ravines, deep valleys, and khors, having generally a direction from east to 
west, enclosing lofty plateaus and terraces ranging from 100 to 700 metres in height, 
and debouching into the Nile. On the east of the axial range other ravines, valleys, 
and khors trend down to the tehama and discharge their intermittent floods into the 
lied Sea, but, in places, the mountain-ridge runs down close to the shore in bold 
escarpments. 
A prominent feature of the Arabian desert is the great depression that crosses it 
between Kenneh and Kosseir, a highway between the Red Sea and the Nile notable 
from time immemorial, which has been frequently described. Klunzinger has recorded 
the following reptiles from in and around Kosseir, viz. : — Gymnodactylus scaler, Ptyo- 
dactylus hctsselquistii, Hemidactylus flavkiridis, H. turcicus, Agama sinaita, Uromastix 
cegyptius, Acanthodactylus boskianns, Eremias guttulata, E. rubropunctata, Chalcides 
ocellatus, Zamenis florulentus, Z. ravergieri, and Lytorhynchus diadema. 
The broad Wadi Arabah, dominated by lofty cliffs, opens into the Gulf of Suez 
near Eas Zafarana, and is memorable as the site of Prof. Schweinfurth's discovery of 
palieozoic rocks l . All of the ravines, wadis, and khors on the western slopes of the 
crystalline ridge of mountains in the Arabian desert north of Eas Benas at Berenice 
preserve much the same general characters as those delineated by Linant de Bellefonds 
as distinctive of the lines of drainage of the Elba group ; but this great area has yet to 
be systematically explored, as it has only been touched at points by a few travellers. 
Schweinfurth 2 has described his visit to the imposing five-peaked Jebel Farageh, about 
1315 metres in height, the Pentadactyle of the ancients, and at the base of which is a 
plain covered with an encrustation of salt derived from the sea in storms. The bare 
summits of this mountain present a remarkable contrast to those of the Elba group, 
which are clothed to their summits with grass and shrubs. The entire mountain is 
more or less covered with gigantic blocks of granite, often as large as houses, or with 
great sheets of granite as smooth as tables, while square jagged masses form dark 
grottoes that serve as hiding-places for gazelles. There are also deep denies. 
Schweinfurth, who attempted, in the month of April, to ascend the highest peak, had 
to abandon his intention about halfway up, owing to the physical obstacles to be 
surmounted and to the intense heat. He was, however, rewarded by many interesting 
plants. This mountain is the southern limit of the distribution of Acacia tortilis. 
The Tropic of Cancer, with the desert which it crosses, not only separates Farageh 
geographically from Elba, but also forms the boundary between a large number of 
plants. The zoology of this area is quite unknown, but when it has been investigated 
it will be interesting to ascertain whether any of the animal species have corresponding 
limits set to their distribution ; however, what is known of the forms found along the 
valley of the Nile does not favour such a supposition. 
1 Bull. Instit. Egyptien, no. 6 (1885). 
2 Zeitsch. Ges. Erdk. 1865, p. 308. 
