108 THE HUMAN SK)E OF BIRDS 



camel, and it is not an inept comparison. They are 

 the best known and most powerful denizens of the 

 desert, and they possess many remarkable features 

 to aid them in their environment. Ostriches have 

 appealed to the imagination since the very earliest 

 times. This fact is borne out not only by monu- 

 ments and inscriptions but by the works of Aris- 

 totle, Pliny, and Xenophon, as well as by the scrip- 

 tiu*es. 



Pliny, as did Aristotle, believed that the bird 

 was part bird and part quadruped. He says: 

 "This bird exceeds in height a man sitting on 

 horseback, can surpass him in swiftness, as wings 

 have been given it to aid it in running; in other re- 

 spects ostriches cannot be considered as birds, and 

 do not raise themselves from the ground. They 

 have cloven talons, very similar to the hoof of the 

 stag; with these they fight, and they also employ 

 them for seizing stones for the purpose of throw- 

 ing at those who pursue them." 



Giant birds, without exception, both living and 

 extinct, are incapable of flight, and they have not 

 that strong bridge-like keel which is found on the 

 breast-bone of a goose, and which is so essential 

 as a support for the powerful muscles of the wings. 

 Whether this incapacity for flight has always been 

 true of the giant birds, or whether it has come about 



