Darwin s Theory of Sexual Selection 205 



continued during many generations, may at last have pro- 

 duced an inherited effect on the vocal organs of the stag, as 

 well as of other male animals ? This appears to me, in our 

 present state of knowledge, the most probable view." 



Here once more we find that Darwin makes use, as a sort 

 of last resort, of the principle of the inheritance of acquired 

 characters. As long as the theory of selection, in any of its 

 forms, appears to offer a satisfactory solution, we find the 

 facts used in support of this theory, but as soon as a diffi- 

 culty arises the Lamarckian theory is brought to the front. 

 It is this shifting, as we have already more than once pointed 

 out, that shows how little real basis there is for the theory of 

 sexual selection. 



The male gorilla has a tremendous voice, and he has, as 

 has also the orang, a laryngeal sac. One species of gibbon 

 has the power of producing a correct octave of musical notes. 



"The vocal organs of the American Mycetes caraya are 

 one-third larger in the male than in the female, and are won- 

 derfully powerful. These monkeys in warm weather make 

 the forests resound at morning and evening with their over- 

 whelming voices. The males begin the dreadful concert, and 

 often continue it during many hours, the females sometimes 

 joining in with their less powerful voices. An excellent 

 observer, Rengger, could not perceive that they were excited 

 to begin by any special cause ; he thinks that, like many 

 birds, they delight in their own music, and try to excel each 

 other. Whether most of the foregoing monkeys have acquired 

 their powerful voices in order to beat their rivals and charm 

 the females — or whether the vocal organs have been strength- 

 ened and enlarged through the inherited effects of long- 

 continued use without any particular good being thus gained 

 — I will not pretend to say ; but the former view, at least in 

 the case of the Hylobatcs agilis, seems the most probable." 



The odor of some mammals is confined to, or more devel- 

 oped, in the males ; but in some forms, as in the skunk, it is 



