266 ON THE RELATIONS OF MAN 



the size of the eye-tooth in the Gorilla being so great that 

 it projects, like a tusk, far beyond the general level of the 

 other teeth. The roots of the false molar teeth of the Gorilla, 

 again, are more complex than in Man, and the pro- 

 portional size of the molars is different. The Gorilla has 

 the crown of the hindmost grinder of the lower jaw 

 more complex, and the order of eruption of the permanent 

 teeth is different ; the permanent canines making their 

 appearance before the second and third molars in Man, and 

 after them in the Gorilla. 



Thus, while the teeth of the Gorilla closely resemble those 

 of Man in number, kind, and in the general pattern of their 

 crowns, they exhibit marked differences from those of Man 

 in secondary respects, such as relative size, number of fangs, 

 and order of appearance. 



But, if the teeth of the Gorilla be compared with those 

 of an Ape, no further removed from it than a Cynocephalus, 

 or Baboon, it will be found that differences and resemblances 

 of the same order are easily observable ; but that many of 

 the points in which the Gorilla resembles Man are those 

 in which it differs from the Baboon ; while various respects 

 in which it differs from Man are exaggerated in the Cyno- 

 cephalus. The number and the nature of the teeth remain 

 the same in the Baboon as in the Gorilla and in Man. But 

 the pattern of the Baboon's upper molars is quite different 

 from that described above (Fig. 17), the canines are pro- 

 portionally longer and more knife-like ; the anterior pre- 

 molar in the lower jaw is specially modified ; the posterior 

 molar of the lower jaw is still larger and more complex than 

 in the Gorilla. 



Passing from the old-world Apes to those of the new 

 world, we meet with a change of much greater importance 

 than any of these. In such a genus as Cebus, for example 

 (Fig. 17), it will be found that while in some secondary points, 

 such as the projection of the canines and the diastema, the 

 resemblance to the great ape is preserved ; in other and most 

 important respects, the dentition is extremely different. 

 Instead of 20 teeth in the milk set, there are 24 : instead 

 of 32 teeth in the permanent set, there are 36, the false 

 molars being increased from eight to twelve. And in 

 form, the crowns of the molars are very unlike those 

 of the Gorilla, and differ far more widely from the human 

 pattern. 



The Marmosets, on the other hand, exhibit the same 



