THE DESCENT OR ORIGIN OF MAN 207 



probable Ihat, through, the law of analogous variation, a 

 member of one of the other lower sub-groups should have 

 given rise to a man-like creature, resembling the higher 

 anthropomorphous apes in so many respects. No doubt 

 man, in comparison with most of his allies, has undergone 

 an extraordinary amount of modification, chiefly in conse- 

 quence of the great development of his brain and his erect 

 position; nevertheless, we should bear in mind that he "is 

 but one of several exceptional forms of Primates. ' ' " 



Every naturalist who believes in the principle of evolu- 

 tion will grant that the two main divisions of the Simiadse, 

 namely, the Catarrhine and Platyrhine monkeys, with their 

 sub-groups, have all proceeded from some one extremely 

 ancient progenitor. The early descendants of this progeni- 

 tor, before they had diverged to any considerable extent 

 from each other, would still have formed a single natural 

 group; but some of the species or incipient genera would 

 have already begun to indicate by their diverging characters 

 the future distinctive marks of the Catarrhine and Platyrhine 

 divisions. Hence the members of this supposed ancient 

 group would not have been so uniform in their dentition, 

 or in the structure of their nostrils, as are the existing Catar- 

 rhine monkeys in one way and the Platyrhines in another 

 way, but would have resembled in this respect fhe allied 

 Lemuridae, which differ greatly from each other in the form 

 of their muzzles," and to an extraordinary degree in their 

 dentition. 



The Catarrhine and Platyrhine monkeys agree in a mul- 

 titude of characters, as is shown by their unquestionably 

 belonging to one and the same Order. The many characters 

 which they possess in common can hardly have been inde- 

 pendently acquired by so many distinct species; so that 

 these characters must have been inherited. But a natural- 

 ist would undoubtedly have ranked as an ape or a monkey 



'^ Mr. St. George Mivart, "Transact. Phil. Soc," 1867, p. 410. 

 '6 Messrs. Murie and Mivart on the Lemuroidea, "Transact. Zoolog. Soc, " 

 vol. vii., 1869, p. 5. 



