288 THE STRUCTURE AND LIFE OF BIRDS CHAP. 



nestling, unless very recently hatched, crawls off on 

 all fours, making much use of not only his enormous 

 feet, but of the great claws that grow at the ends of 

 the two first digits of his hand. If you try to pull 

 him from the nest by the legs, he holds fast by means 

 of these wing-claws and his beak. Often a young 

 bird may be found clawing his way onward some 

 distance from the nest. If he tumbles into the water 

 he proves to be a born swimmer and diver. All this 

 is so astonishing that some people are inclined to 

 hesitate before they accept it as true. But the paper 

 by Mr. J. J. Quelch, from which I derive this account 

 of the bird's habits, is based upon patient and careful 

 observation. Nor does the Hoatzin, so far as his 

 infant mode of life is concerned, stand absolutely 

 alone. The young Ionornis, a Florida bird, has been 

 seen to climb out of his nest by means of his wing- 

 claws, 1 and besides this the anatomy of the young 

 Hoatzin bears witness to his habits. The wing-digits 

 are enormously developed. I have already mentioned 

 that the embryo has a distinct rudiment of a fourth. 

 More remarkable is the great length of its first. 

 Though No. 2 is of wonderful dimensions, yet No. I 

 is more than half its length. And each of these two 

 carries at its end a very big claw. Contrast with them 

 the digits of a Swift's wing ; there we find the first 

 hardly more than a quarter of the length of the second, 

 and there is no sign of a claw on either. 2 In the 



1 Shufeldt, Ibis, vol. ii., 1890. 



2 The hand of the embryo Hoatzin is here compared with 

 that of an adult Swift. The hand of an embryo Swift would 

 probably present a very great, though not so great, a contrast. 



