360 SAVAGE SUDAN 



The pied crows (Corvus scapulatus) were also breeding in the 

 hills. One nest on March 29th, with two young, was in a "pot-hole" 

 of a gigantic granite boulder, a regular kaaba, 18 feet high, that lay 

 stranded on the plateau ; a second, the next day, was built in a thorn- 

 tree and contained five speckled blue-green eggs. 1 



Blue rock-doves, paler than ours, bred in isolated jebels, and so 

 also did crag-martins and white-rumped swifts ; while in the mimosas 

 turtle-doves (Turtur roseigriseus) had eggs by early in April. 



The above represent some few of the chief types of bird-life among 

 the hills. Many other species could be added coursers, stone-curlews, 

 sand-grouse, pallid harriers, eagle-owls (Bubo cinerascens), a single little 

 owl (Athene noctua) rather beyond his true latitude, and falcons, 



PIED CROW SARROWIT. 



but will conclude this chapter with following note from diary: 

 "Throughout the sandy and rocky deserts of Northern Sudan one 

 notices, region by region, corresponding changes in the depth of 

 monotone colours, darker or paler, prevalent in bird and beast. Thus 

 on the tawny deserts beyond Omdurman both Certhilaudas and 

 Pyrrhulaudas are markedly paler than those on this darker Erkowit 

 plateau; while an intermediate phase (of different ground-colour) 

 occupies the Red Sea littoral. Another eloquent example of graduated 

 adaptation to altering environment is afforded by the sandy-hued 

 Ammomanes : and hardly less so by the desert -babbler (Argyd), both 

 of which are found alike on sandy and on rocky deserts, and in each 

 locality exquisitely corresponding with their immediate surroundings." 



1 Near the Iron Gates on White Nile, two pairs of pied crows had built 

 a twin eyry in a 1 5-foot thorn-tree, and the owners sat incubating hardly a 

 foot apart. This was on March I2th, 1919. 



