I 12 



The Bird 



It may seem to us that the mandibles, the jugal, the 

 palate, the quadrates, the ear-bones, and the hyoid are 

 an unmeaning jumble of irregular bones, apparently 



bearing no relation to one another, 

 and with absolutely no interest 

 outside the fact that each is very 

 well suited to its particular use. 

 If scientists had studied only the 

 bones of adult animals, we might 

 have groped in vain for any an- 

 swer to the question of how these 

 bones came to be what they are. 

 But the science of embryology, or 

 egg-life, has unfolded wonderful 

 things, and, as w^e shall soon see, 

 nothing more marvellous than the 

 strange story of these bones. / 



The eel-like lampreys which 

 crowd up our shallow brooks in 

 April to spaw^n are curious crea-- 

 tures, and not the least remark- 

 able thing about them is the fact 

 that they have no jaws, although 

 they have an elaborate cartilagi- 

 FiG.86.-Gill-basket of Lamprey. ^^^^^ net-work protecting and 



supporting the gills. We perhaps thought that every 

 vertebrate animal in the world had jaws of some kind, and 

 perhaps even lampreys had them long ago, before their 

 habit of sucking did away with any need for chewing. 

 But the reason I have spoken of the lamprey is because 



