Ill 



Human Skulls com/pared 



The Skull. 



The Jaws. 



But we have one most important inquiry yet to prosecute, 

 and that is the comparison of the skull in apes with that of 

 man. Beginning w ith the anatomy of the facial portion, it may 

 be observed that the jaws are long and narrow, or dog-like, in 

 the inferior monkeys ; shorter in apes, though still very progna- 

 thous ; shorter still, considerably, in even the lowest races of 

 mankind, in whom, however, the jaws protrude considerably 

 as in Negritos in Java, Andamanese, African Negroes, and 

 Australian Aborigines. In the higher races of mankind the 

 jaws are shorter and more arched, and assume the form which 

 has been called orthogoathous. 



The lower jaw in the higher races of man has a prominent 

 chin, which is almost absent in the lower races, and is obsolete 

 entirely in apes. 



The Teeth. 



The teeth in man and apes are the same in number, namely, 

 eight on each side in both jaws. The apes, generally, have the 

 canine. teeth large and strong, and separated from their neigh- 

 bouring teeth, the incisors or pre-molars, by a space, to permit 

 the one canine tooth to pass the other. This space is called a 

 diastema. All the apes have a considerable diastema except 

 the female chimpanzee and a species of orang in Borneo, in 

 whom it is small, because they have small canines. 1 These 

 characteristics in the face of apes — their prognathism and the 

 prominence of their canine : teeth — have all relation to their 

 rapacious and warlike propensities, and to the nature of their 

 food. Even in the higher races of man, however, the prominence 

 and projection of the canines beyond the level of the other 

 teeth is often remarkable. 



The molars, or back grinding teeth, in apes are the same in 

 pattern as those of man. In man the last molar, or " wisdom 

 tooth," is smaller than the other molars ; so is it with the 

 chimpanzee and orang, and with the fossil Palwopithecus, found 

 in Northern India ; but not so with the gorilla, in which it is 

 larger. In succession, the grinders are, in the apes, cut before 

 the incisors. With man the converse is the case. 2 The inner 

 upper, and outer lower incisors are wider than their neighbour- 

 ing incisors, both in apes and man. 



1 Owen's " Odontography," text p. 444, PI. 117, fig. 4. 



2 Professor Owen, in " Longmans' Magazine " for November, 1882. 



