398 THE LIFE OF A BIRD. 



pieces sticking out laterally from the shaft, and 

 arranged with their flat faces to each other. These 



are held together by the barbules, which are 

 attached to each side of them, so that when the 

 barbs lie together, the barbules form a series of 

 little hooks, which hold them close to each other. 

 In consequence of the direction in which these 

 barbules are placed, no fastening can be more 

 secure. It has also the advantage of being self- 

 acting, so that wheo the barbs are forcibly sepa- 

 rated from each other, the moment they are 

 returned, and brought together again, these little 

 hooks interlock, and all is as firm as it was before. 



