480 The Bird 



begin to be seen, looking, however, more like tiny cones 

 than anything else (Fig. 11). The muscles and the cartilage 

 skeleton are well defined on the fourteenth day, and about 

 this time the tiny beak with its white egg-tooth is pressed 

 against the membrane of the air-chamber at the large end 

 of the egg. Reptiles also show this tiny bit of sharp lime 

 upon the head, which drops off soon after its function is 

 completed. Not until almost the last day is the mem- 

 brane pierced and the first gasp of air breathed into the 

 little lungs. By an instinctive moving of the head back 

 and forth the shell is filed through and cracked, and the 

 chick rolls out into the world, weak and helpless and for 

 a while absolutely dependent upon warmth and the care 

 of its mother, before it is fit for its future life. (Figs. 18 

 and 19.) 



Thus do all wild birds begin life, passing through 

 similar phases within the egg; and although we so often 

 admire a nest full of eggs, yet how seldom do we give 

 thought to the tiny creatures within, their hearts even 

 at that very minute, perhaps, giving their first fluttering 

 beat! 



The instant that its eyes have cleared and its shaky 

 legs have gained strength to support its body, the chick 

 begins to use its senses and to store up experiences, taking 

 note of this sound and that taste, learning to fear or to 

 ignore, to flee or to pursue, to call or to remain silent. 

 And thus does the brain of the chick and of all wild nestlings 

 begin to act and its psychological life commences, with 

 intermingled perceptions, instincts, and gleams of intelli- 

 gence. Here belong the making of nests and journeys, 



