Ornithology of Northern Africa. 283 



adult hue, or the bird of the snowy peaks of the Alps may become 

 assimilated in colour, while in the Sahara he reflects the pre- 

 vaihng tints around him. The Lammergeyer^s favourite food 

 [reptilia) abounds in the Desert, and his rare occurrence at any 

 distance from the mountains is therefore the more remarkable, 

 unless it be that he is more loath than the Grifl"on to exercise the 

 powers of flight which he certainly possesses. The Lammer- 

 geyer is, by comparison with the Grifibn, a stupid bird, as well 

 as an unsociable one; rarely more than two or three are seen 

 together. But in its flight it is the most majestic of birds : sail- 

 ing like a Falcon, he will skim for miles without any perceptible 

 motion of the wings, stilly gliding through space till lost to the 

 telescope ; then, returning, he will turn the sharp corner of a 

 cliff" in the gorge, just bending his long cuneate tail, one wing 

 gently drawn-in like the Falcon's, and as gently again expanded. 



5. Aquila chrysaetos. (Golden Eagle.) 



I never observed this bird in any of the cliff's by the ' Weds ' 

 or mountain ranges of the Desert ; but in the Dayats it abounds. 

 It might almost be said to be gregarious, especially in the 

 Dayat of Tirehmet, a day's journey north of Berryan in the 

 M'zab. The wood here extends over many acres ; and I saw no 

 less than seven pairs of Golden Eagles, who had each their nest. 

 There were many other unoccupied nests ; in fact, there were 

 few Terebinths of any size without a huge platform of sticks on 

 the topmost boughs. Many of the smaller Dayats were tenanted 

 in like proportions. Any zealous oologist might collect in this 

 region the eggs of 50 nests in a month, could he obtain a suf- 

 ficient supply of water to enable him to remain ; but the neces- 

 sity of sending a four days' journey for water may preserve this 

 colony undisturbed for many years to come. The Gazelles and 

 Sand-grouse who resort to the Dayats are probably a sufficient 

 supply for the Eagles and Kites who reside here, and the im- 

 possibility of finding other nesting-places may render the Eagles 

 less tenacious of their domains. Being undisturbed, they are 

 very fearless ; and 1 twice walked under a tree and brought 

 down a fine specimen with No. 7 shot. 



6. CiRCAETUs GALLicus. (The Short-toed Eagle.) 



This Eagle came only once under my observation in the De- 



