THE TEETH OF PRIMATES. 415 



The wisdom teeth present the same pattern of grinding 

 surface, are larger than the other molars in the gorilla 

 and the orang, and there is abundant space for them, so 

 that they play an important part in mastication. The 

 molar teeth of these apes are also squarer, their cusps 

 sharper and longer, and the characteristic patterns more 

 strongly pronounced, than in man. 



Anthropidae. In passing from the highest of the apes 

 to the lowest of mankind, there is a sudden change in the 

 character of the dentition ; but while it cannot but be 

 admitted that there is a gap, yet the differences are rather 

 of degree than of kind. 



Even in the lowest of human races the facial angle is 

 greater, that is to say, they are much less " prognathous " 

 than the apes, and the upper and lower incisors are more 

 nearly vertical in position, not meeting one another at such 

 an angle as in the apes. Mr. Perrin (Monthly Review Dent. 

 Surgery, 1872) states that in a gorilla skull there is an inch 

 of bone in front of the anterior palatine foramen : in a negro 

 half an inch, and in a Greek skull it was close behind the 

 incisors. 



Ifc is generally said that in man the molars decrease in 

 size from before backwards ; that is to say, that the first 

 molar is the largest, while in anthropoid apes the contrary 

 is the case. Though this is on the whole true, it requires 

 some qualification : thus in certain lower races, such as the 

 Australian blacks, the second and third molars are not 

 smaller than the first, and of the chimpanzee the same 

 thing may be said. 



There is no diastema ; no sexual difference in dentition ; 

 no tooth projecting beyond its fellows, and the teeth are 

 arranged in an unbroken arch. The premaxillary bones 

 become fused with the superior maxillary early in- life, 

 whereas^ in the Quadrumana they remain distinct. 

 \, In general terms it may be said that the dentition of th 



