TAILED MONKEYS. 



43 



The chest is always flattened at the sides, 

 not broad as in the anthropoid apes. 

 Although the dental formula 



/2 . I . 2 . T. 



2.1.2.3 



is the same in all tailed monkeys as in man 

 and the anthropoid apes, yet there are con- 

 siderable variations within this formula, 

 variations which, apart from the definite 

 form, are partly due to age partly to sex. 

 From the herbivorous Semnopitheci, whose 

 constricted stomach, almost adapted for ru- 



Fig. 2. The White-handed Gibbon (Hylobatcs lar}. 



minants, plainly shows what they are 

 intended for in this respect, and whose 

 nearly square molars soon lose by friction 

 their blunt knobs or tubercles, there is a 

 long series of gradual modifications till 

 we rise to the Cynomorpha;, and more 

 particularly the Gelada, in whose frightful 

 jaws the long narrow laterally compressed 

 molars with four sharp tubercles when 

 seen from the side present exactly the 

 appearance of the dentition of a carnivore. 

 The last molar is sometimes larger, some- 

 times smaller, sometimes with four, sometimes 

 with five tubercles, but these differences do 

 not appear to have any influence on the rest 

 of the organization. 



As regards the significance to be attached 

 to the canines it is necessary to be very 

 cautious. If the enormous, sharp, curved 

 canine with sharp cutting edge behind in the 

 upper jaw of the Cynomorpha;, and above all 

 in the gelada, can scarcely be matched even 



