THE EAR IN MAN AND APES. 2/1 



became rudimentary and useless. We still, however, possess 

 them (Fig. 250). A few individual men can even move their 

 ears forward or backward a little by the use of the forward 

 muscle (6) and the backward muscle (c) ; and by long 

 practice these motions can be gradually increased. On the 

 other hand, no man is able to erect the ear-shell by the 

 upward muscle (a), or to change its form by the little inner 

 muscles of the ear (d, e, f, g\ These muscles, which were 

 very useful to our ancestors, have become entirely un- 

 important to us. This is equally true of Anthropoid Apes. 



We also share only with the higher Anthropoid Apes 

 the Gorilla, Chimpanzee, and Orang the characteristic form 

 of our human ear-shell, especially the rolled edge, the helix, 

 and the ear-flap. The lower Apes, like all other Mammals, 

 have pointed ears without the helix, and without ear-flaps. 

 Darwin has, however, shown that in some men a short, 

 pointed process, not occurring in most individuals, is per- 

 ceptible at the upper part of the folded rim of the ear. In 

 some few individuals, this process is very well developed. 

 It can only be explained as the remnant of the original 

 point of the ear which, in consequence of the folding of the 

 edge of the ear, has been bent forward and inward. 

 (Of. the similarly folded ear in the embryo of the Pig 

 and Cow, Plate VII. Fig. H ill. and C in.) On carefully 

 comparing the ear-shells of Man and of the various Apes in 

 this particular, we find that they form a connected series of 

 retrograde steps. In the common catarhine ancestors of tho 

 Anthropoids and of Man, this retrogression began with the 

 folding down of the ear-shell. In consequence of this, tho 

 ear-edge was formed on which that significant corner 

 appears, the last trace of the free prominent point of the ear 

 51 



