242 THE ZOOLOGIST. 



leaves or consisting of little more than thorny twigs. For mile 

 upon mile the way leads over a gently undulating expanse of 

 stony desert, where the only living things are sandy-coloured 

 Lizards and Mantids, darting about with prodigious swiftness, 

 and probably feeding on the few minute flies which somehow 

 contrive to find subsistence here. The view is shut in by the 

 gently rising ground, and though every sky-line gives promise of 

 a changing scene, it is a promise which rarely finds fulfilment. 



The desert is not, however, by any means all flat or even 

 undulating, but the level plain may give place to more broken 

 ground with bold rocky cliffs, which often show curious effects 

 of the tremendous weathering power of blowing sand and 

 extremes of heat and cold. 



Once out on the true desert, practically all bird life is left 

 behind. Here and there, near the edge of it, a little flight of 

 Pipits passes by seeking the patches of vegetation, and birds of 

 strong flight, such as Eavens, Vultures, and Swifts are occasion- 

 ally seen. The Swift {Cypselns pallidas) may be found nesting 

 in rock crevices in the desert some miles south-west of Dahchour. 

 With these exceptions there appear to be no birds resident in 

 these wastes, in spite of the fact that there is a scanty insect 

 fauna subsisting on one knows not what. 



It is only in the immediate neighbourhood of the Nile valley 

 that birds are met with in any numbers, the cliffs that bound 

 the valley being a favourite nesting-haunt of many of the birds 

 of prey. These cliffs are composed of limestone, and their line 

 is broken in various places by deep gorges running in for a 

 considerable distance. These narrow gorges are closed in by 

 precipitous walls of rugged rock terraced by ancient water levels, 

 and often honeycombed with water-worn caves and holes of all 

 sizes, many of which have been the abode of Neolithic man or 

 of persecuted Copts, and some of which may even now be the 

 homes of lawless or outlaw Arabs. 



The ledges and holes in these steep and almost inaccessible 

 cliffs make admirable nesting-places for birds of prey, or dens 

 for Jackals. It is here that the Griffon and Egyptian Vultures 

 and Bonelli's Eagle nest, and Ravens and Falcons may be seen 

 in most of these gorges in the spring. The Rock Swallow (Cotile 

 obsoleta) flits about the bare rocks in some numbers, and now 



