THE TURKEY 93 



may be that we owe to it the fable of the " roc " (with 

 which every reader of the Arabian Nights must be 

 familiar), since it is a very natural error to suppose 

 that the size of a bird must correspond proportionally 

 with that of its egg. 



But it is New Zealand which is justly the most cele- 

 brated country for its extinct birds. Till man visited it 

 no beasts save bats dwelt there, and those gigantic birds, 

 the moas [Dinornis), lorded it over all other living 

 creatures, and stalked about in absolute security, without 

 the power or need of flight, till man came and extermi- 

 nated them. There also was once to be found a large 

 bird of prey, known as Harfagornis, which had more 

 powerful claws than any existing eagle possesses. 



But all the extinct species yet mentioned must 

 be reckoned as relatively modern forms of life. When, 

 however, we descend the stream of time and explore 

 the rocks deposited in past geological ages, we find 

 unmistakable evidence that birds once existed which 

 were very different indeed from any of those which 

 people the surface of our planet in the present day. 

 Nevertheless, as we recede we find the change which 

 has taken place to have been a gradual process of change. 

 In the Pliocene rocks we meet only with genera which 

 now exist, nor are we struck with any marked geo- 

 graphical changes. But in Miocene times, trogons and 

 parrots dwelt in Europe, but not the turkey, which even 

 then seems (as befoi-e said) to have been an exclusive 

 inhabitant of America. 



When we penetrate into the Eocene rocks, however, 

 we find genera altogether new, although allied to such 

 birds as larks, kingfishers, vultures, woodpeckers, &c. 

 The exploration of the secondary rocks, has, as might 

 have been expected, brought much stranger forms to light. 



