Chap. I.] RUDIMENTS. 23 



accessory muscles and other structures, is especially well 

 developed in birds, and is of much functional importance 

 to them, as it can be rapidly drawn across the whole eye- 

 ball. It is found in some reptiles and amphibians, and in 

 certain fishes, as in sharks. It is fairly well developed in 

 the two lower divisions of the mammalian series, namely, 

 in the monotremata and marsupials, and in some few of 

 the higher mammals, as in the walrus. But in man, the 

 quadrumana, and most other mammals, it exists, as is ad- 

 mitted by all anatomists, as a mere rudiment, called the 

 semilunar fold. 20 



The sense of smell is of the highest importance to the 

 greater number of mammals — to some, as the ruminants, 

 in warning them of danger ; to others, as the carnivora, in 

 finding their prey ; to others, as the wild-boar, for both 

 purposes combined. But the sense of smell is of ex- 

 tremely slight service, if any, even to savages, in whom it 

 is generally more highly developed than in the civilized 

 races. It does not warn them of danger, nor guide them • 

 to their food; nor does it prevent the Esquimaux from 

 sleeping in the most fetid atmosphere, nor many savages 

 from eating half-putrid meat. Those who believe in the- 

 principle of gradual evolution, will not readily admit that 

 this sense in its present state was originally acquired by 

 man, as he now exists. No doubt he inherits the power 

 in an enfeebled and so far rudimentary condition, from 

 some early progenitor, to whom it was highly serviceable 

 and by whom it was continually used. We can thus 

 perhaps understand how it is, as Dr. Maudsley has truly 



28 Miiller's 'Elements of Physiology,' Eng. translat., 1842, vol. ii. p. 

 1117. Owen, 'Anatomy of Vertebrates,' vol. iii. p. 260; ibid, on the 

 Walrus, ' Proc. Zoolog. Soc.' November 8, 1854. See also R. Knox, 

 Great Artists and Anatomists,' p. 106. This rudiment apparently is 

 Bomewhat larger in Negroes and Australians than in Europeans, see Carl 

 Vogt, • Lectures on Man,' Eng. translat. p. 129. 



