The Zoologist — November, 1868. " 1437 



extreme daring, is omnipresent, and trusts generally to sight, as it will 

 stoop at a piece of red cloth in mistake for flesh ; thus proving that it 

 depends more upon vision than smell. 



" No. 3 is the red-faced small vulture. 



" No. 4 is the large bare-throated vulture. 



" No. 5 the Marabou stork, sometimes accompanied by the ad- 

 jutant. 



" When employed in watching the habits of these birds, it is 

 interesting to make the experiment of concealing a dead animal 

 beneath a dense bush. This I have frequently done ; in which case 

 the vultures never find it, unless they have witnessed its death ; if so 

 they will already have pounced in their descent while you have been 

 engaged in concealing the body : they will then, upon near approach, 

 discover it by the smell. But, if an animal be killed in thick grass, 

 eight or ten feet high, the vultures will seldom discover it. I have 

 frequently known the bodies of large animals, such as elephants and 

 buffaloes, to lie for days beneath the shade of the dense nabbuk 

 bushes, unattended by a single vulture ; whereas, if visible, they would 

 •have been visited by these birds in thousands. 



" Vultures and the Marabou stork fly at enormous altitudes. I believe 

 that every species keeps to its own particular elevation, and that the 

 atmosphere contains regular strata of birds of prey, who, invisible to 

 the human eye at their enormous height, are constantly resting upon 

 their wide-spread wings, and soaring in circles, watching with tele- 

 scopic sight the world beneath. At that great elevation they are in 

 an exceedingly cool temperature, therefore they require no water; "but 

 some birds that make long flights over arid deserts, such as the Mara- 

 bou stork and the bustard, are provided with water-sacks ; the former 

 in an external bag a little below the throat, the latter in an internal 

 sack, both of which carry a large supply. As the birds of prey that 

 I have enumerated invariably appear at a carcase in their regular suc- 

 cession, I can only suggest that they travel from different distances or 

 altitudes. Thus the Marabou stork would be farthest from the earth ; 

 the large bare-necked vulture would be next below him, followed by 

 the red-faced vulture, the buzzard, and the crow that is generally about 

 the surface. From their immense elevation the birds of prey possess 

 an extraordinary field of vision ; and although they are invisible from % 

 the earth, there can be no doubt that they are perpetually hunting in 

 circles within sight of each other. Thus, should one bird discover 

 some object upon the surface of the earth below, his sudden pounce 



