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idse or Man-like Monkeys), and the Anthropida (Hominidae 

 or Men). The Cynoraorpha and the Anthropomorpha 

 together constitute the group Catarrhini. 



Of these the Arctopitheci probably diverged first from 

 the ancestral Primates. They form a small group which 

 has not undergone any great modification. The Platyrrhini 

 and the Catarrhini shew very marked differences, and con- 

 sequently must have diverged greatly from the common 

 ancestral series. Probably the Platyrrhine branch was given 

 .off first, and it has not risen to so high a level of organisa- 

 tion as the remaining Primates have. 



The common ancestors of the Catarrhini and the 

 Anthropida, after the separation of the primitive Platyrrhini, 

 must have acquired the narrow partition between the nostrils 

 and the arrangement of teeth characteristic of man and 

 some of the higher monkeys. This ancestral series then 

 gave rise to two divergent lines of descent, the one leading 

 to the Catarrhini, and the other to the first men. 



The Catarrhine branch probably split at an early period 

 into two parts — a lower, which has resulted in the Cyno- 

 morpha, a group containing all the ordinary Old-World Apes, 

 quadrupedal forms with ischial tuberosities and usually a 

 long tail ; and a higher, represented by the Anthropomorpha 

 or Anthropoid Apes, which assume a semi-erect position 

 and have no tail. This last group includes four genera 

 which are decidedly the highest of Apes, and those which 

 approach most nearly to the Anthropida, although, as may 

 be seen from the table, they are not in any sense ancestral 

 forms. They are: Troglodytes (the Chimpanzee), Gorilla, 

 Simla (the Orang), and Hylobates (the Gibbons). 



The Anthropida, the highest product of evolution, pro- 

 bably arose from the ancestral Catarrhini. It is possible, 

 however, that the point of origin was on the Catarrhine 

 branch, near the place where the Cynomorpha and Anthropo- 



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