486 THE INDIVIDUAL AND THE RACE: 



(b) The persistence of antiques is often seen with dia- 

 grammatic vividness in the case of vestigial structures, which 

 linger on in dwindled expression for ages after they have 

 ceased to be of any use. As Darwin said, they are like 

 the unsounded letters in many words, quite functionless 

 but of historical interest. They have often been compared 

 to the vestigial structures in clothes, buttons without cor- 

 responding holes, and holes without corresponding buttons. 

 So is it with the deeply-buried remnants of the long lost 

 hind limbs that some of the whales still exhibit, or with 

 the minute comb-like vestige of a gill in the spiracle of a 

 skate. The animal world is full of these interesting relics 

 as if the past were loath to relinquish its lien on the present. 

 Man is an antiquarian in spite of himself, a walking museum 

 of relics. A good instance is the vestigial third eyelid, larger 

 in some races than others, occasionally with a supporting 

 cartilage, but quite useless. It is the remnant of the nicti- 

 tating membrane that in most birds and mammals does im- 

 portant work in cleaning the eye. Similarly, the muscle 



t 



which moves the trumpet or pinna of the ear in many mam- 

 mals, such as dog and donkey, and is useful in locating 

 sounds, is vestigial in man, who moves his head about so 



7 O / 



readily. Some men have it larger than others ; some may 

 even become able to move their ears by wasting attention 

 on the senseless effort. It may be noted that there is no 

 great evidence of imperfection in the fact that vestigial 

 organs are sometimes troublesome; it is too much to expect 

 that there should be no tax on the stability of what is 

 useful. 



Another instance of the past living on in the present is 

 to be found in the persistence of ancient habits that have 

 outlived their utility. According to Darwin, there is an 



