Hairs and Feathers. Cl 



each of these latter is held in its place by several 

 hooks. Thus they are not easily pulled asunder, and 

 the last thing to yield is the tapering point which the 

 hooks pass with a jerk. 



You will also see that the tapering points belong- 

 ing to the filaments turn up a little ; this adds to 

 the firmness with which the latter are held by the 

 hooks. The hooked filaments are set near the upper 

 edges of the plank- shaped shafts ; the knife-like fila- 

 ments on the opposite sides are lower down, and both 

 stand out very stiffly. 



Thus the natural position of these hooks is above 

 the neighbouring row, and duly fastened to it. When 

 we begin to smooth down the feather, the filaments 

 cannot fail to clasp each other. They do it, like a 

 released spring, in the act of straightening themselves, 

 and when they have resumed their natural shape the 

 feather has regained its beautifully level smoothness. 

 Such are the curious self-acting hooks on the feathers 

 of birds. 



