no ARE THE EFFECTS OF USE INHERITED? 



suspend one's judgment as to the true explanation 

 of highly exceptional and purely pathological cases 

 rather than resort to an hypothesis that creates more 

 difficulties than it solves. 



THE MOTMOT'S TAIL. 



The narrowing of the long central tail 

 feathers of the motmot is attributed to the in- 

 herited effects of habitual mutilation (Descent of 

 Man, pp. 384, 603). But in the specimens at South 

 Kensington l the narrowness extends upwards 

 much beyond the habitually denuded part, and the 

 broadened end is the broadest part of the whole 

 feather. If the inherited effect of an inch or 

 two of denudation extends from three to six inches 

 upwards, why has it not also extended two inches 

 downwards so as to narrow the broadened end ? 



1 Natural History Museum, central hall, third recess on the 

 left. 



