PARTS OF ANIMALS, IV. xii. 



they have few parts which differ from one to another. 

 But as compared with other animals, they differ in 

 respect of the form of their parts. One pecuHarity 

 of the birds is that they all have feathers, whereas 

 in other animals the parts are covered with hair, or 

 scales, or horny plates. A bird's feather is split, and 

 therefore different in form from the wing of certain 

 insects, which is undivided ; as well as having a shaft, 

 whereas the insects have none. Another peculiarity 

 of birds is the beak, an extraordinary appendage to 

 the head. It is made of bone, and serves them 

 instead of teeth and lips, just as the elephant's trunk 

 takes the place of hands, and the tongue of certain 

 insects replaces a mouth. We have spoken already 

 of the sense-organs.^ 



Birds have a neck which sticks up, and for the same 

 reason that other creatures have one. Some have a 

 long neck, some a short one : in most of them it corre- 

 sponds in length fairly closely to the legs, so that the 

 long-legged birds have a long neck and the short- 

 legged birds a short neck (web-footed birds excepted.) 

 WTiat assistance in getting food out of the ground 

 would a short neck be to a bird on long legs, or a long 

 neck to a bird on short legs ? Furthermore, the 

 carnivorous birds would find a long neck a real dis- 

 advantage in their daily life. These birds depend 

 for their livelihood on superior strength, and length 

 of neck means lack of strength ; so no crook-taloned 

 bird has a long neck. Web-footed birds, how- 

 ever, together with others in the same class whose 



° In Book II. chh. 12 fF. 



2 Se Langkavel : ye Y6 : om. vu\g. 



^ av ^v PY6, Ogle : om. vulg. 



* <Ta> Ogle. 



403 



