EVEN GROWTH OF FEATHERS 125 



ever it occurs ; it will be noticed that except in 

 the case of the Penguin, these methods of fledging 

 are only found in families which have active chicks. 



The third method of fledging is that which occurs 

 in the vast majority of birds, and is what one 

 would have reasonably expected in all of them ; 

 that is to Say, the feathers grow pretty evenly all 

 over the body, and the wings develop in size like 

 the legs, and grow their quills pretty nearly as 

 quickly as the body-feathers, and much more so 

 than the tail, which goes ahead in the case of the 

 retarded fledgers of the Duck and Rail type ; our 

 Pigeons, Doves, Canaries, and Budgerigars furnish 

 familiar examples of this, as well as such wild birds 

 as Thrushes, Sparrows, etc. 



But these are all birds with helpless young ; and 

 the uniform method of fledging, being so prevalent, 

 is also found among birds whose chicks are active, 

 such as Plovers and Gulls. Some people, indeed, 

 regard the young Gull as intermediate between the 

 active and passive type of young bird ; but as it is 

 able to walk about, even when quite small, and can 

 pick up the food the parent vomits for it, even if 

 it does not provide for itself, it can fairly claim 

 to be put on the active list. 



It is, however, often hatched in a nest which 

 puts pedestrian exercise out of the question, as 

 when this is on a ledge of a cliff, and so there is 

 certainly a tendency in young Gulls to degenerate 

 towards the passive type. This is so also with their 

 diving relatives the Auks, but even these, cliff- 



