branches. Should he fall, by some mischance, into the water, 

 he promptly swims to the bank ; and by the aid of his long 

 first finger, and wing-claws, and his huge feet, soon climbs 

 back. But the most wonderful part of his story is yet to come. 



So long as these youngsters can only scramble about they 

 are in constant jeopardy. A wing-surface at least big enough to 

 break the force of a fall is an urgent necessity. And so the 

 growth of the quill-feathers is, so to speak, pushed forward with 

 all possible speed. But if all the feathers grew at the same 

 rate, there would speedily come a time when the outermost 

 feathers would make the claw at the end of the finger useless, 

 while the wing-surface, as a whole, would be insufficient. To 

 obviate this difficulty, the development of the outermost feathers 

 is held in abevance till the inner feathers of the hand, and the 

 outermost of the forearm, have grown big enough to suffice to 

 breake the force of the fall. As soon as this stage is arrived at, 

 the outermost quills, whose growth has been held in abeyance, 

 rapidly develop ; the finger decreases in length, and its claw 

 disappears, while that of the thumb soon follows suit. And thus 

 it comes about that the hand, in the nestling, is relatively much 

 longer than in the adult. But in its mid-period it may be taken to 

 represent the adult stage of the wing of the ancient Archseopteryx. 

 This bird could have been but a poor flier, and probably during 

 the time it was moulting its quills it was absolutely flightless. 



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