180 THE EVOLUTION OF MAN. 



from the former by the formation of the characteristic 

 catarhine head, and by the peculiar modification of the 

 teeth, the nose, and the brain. This oldest parent-form of 

 the whole Catarhine group must, certainly, have been 

 thickly covered with hair, and must have had a long tail ; 

 was, in fact, a Tailed Ape (Menocerca, Fig. 203). They 

 were already in existence during the earlier part of the 

 Tertiary Epoch (during the Eocene Period), as is shown by 

 fossil remains of Eocene Catarhines. Among extant Tailed 

 Apes, the Slender Apes (Semnopitheci) are perhaps most 

 nearly related to this parent-form. 168 



As the twentieth stage in the human pedigree, next to 

 these Tailed Apes, we must rank the Tail-less man-like Apes 

 (Anthropoides), under which name the most highly de- 

 veloped Catarhines, those most nearly related to Man, have 

 been grouped. They originated from the Tailed Catarhines, 

 by the loss of the tail, the partial loss of their hairy cover- 

 ing, and the further development of the brain, the latter 

 being indicated in the preponderating development of the 

 brain-skull over the facial skull. At the present time but 

 few forms of this remarkable family are in existence ; they 

 are distributed into two different groups, an African and an 

 Asiatic group. The African Man-like Apes are limited to 

 the western part of tropical Africa, but are probably dis- 

 tributed over Central Africa in several species. Only two 

 species are well known: the Gorilla (Pongo gorilla, or 

 Gorilla engina), the largest of all Apes (Fig. 207) ; and the 

 smaller Chimpanzee (Pongo troglodytes, or Engeco troglo- 

 dytes), which may be seen in several zoological gardens 

 (Figs. 206, Plate XIV. Figs. 1, 2). Both the African Man- 

 like Apes are black in colour, and like their countrymen, 



