236 WITH THE U. S. NATURALISTS 



''They're pretty small, too. Gadow once 

 counted the barbules of one of the primary 

 feathers of a Crane, and found that each barb on 

 the inner side of the vane bore six hundred pairs of 

 barbules and that there were a thousand barbs, 

 or more than a million barbules for each feather. 

 So you see, my boy, when a feather may have as 

 much as half a million little hooks and eyes to 

 keep it in place, it is no wonder that the bird's 

 feather coat fastens around to keep him snug and 

 warm and that the feathers do not ruffle up in the 

 wind. It is the absence of these booklets on the 

 barbules of certain feathers — such as the Ostrich 

 plumes — which gives them their fluffy and floating 

 character. 



"Feathers, like all other things, need to be kept 

 in order, and you've watched birds enough, Shan, 

 to have noticed how carefully they preen their 

 feathers. Nor is this vanity, alone, for the life of 

 most birds depends on their power of flight and 

 this, in turn, depends on the effectiveness of the 

 feathers. Thus water-birds not only preen their 

 feathers very carefully, but, from glands near the 

 tail, they press out oil with their bills and they 

 oil their feathers with this. 



*'Most birds are able to comb their feathers 



