THE EVOLUTION OF THE MAMMALIA. 249 
lower jaw and the prominent chin. The lower jaw is horseshoe shaped, and its 
two firmly coossified halves enclose a much broader space for the tongue than 
in any of the apes. In number and form of the teeth the dentition corre- 
sponds with that of the Old World apes, but the canines hardly project above 
the level of the unbroken row, and the cusps of the grinding teeth are lower, 
broader, and less pointed than in the apes. * 
"Important peculiarities of the backbone and limbs produce man's erect 
gait. These are the double, S-like curvature of the backbone, the elonga- 
tion and powerful musculature of the legs, the breadth of the shoulders, and 
the relative shortness of the arms. The human hand far surpasses in mobility 
and adaptability that of any ape ; the thumb is strongly developed, opposable 
and very mobile. The sole of the foot is horizontal. The ankle and instep 
bones form an arch, and the strong, non-opposable great toe cannot be used 
for grasping, but only to carry the weight of the body. 
" In his whole anatomical structure and bodily development man undoubt- 
edly belongs to the Primates, and if he is often assigned a position outside of 
the animal kingdom, this assignment does not rest upon the facts of bodily 
structure, but upon his high intellectual capacities, upon the possession of 
mind and articulate speech." 1 
These are simple statements of fact, to which no one can take 
exception, but the questions of man's ancestry cannot be satis- 
factorily answered, despite the optimistic statement attributed to 
Haeckel, that " there are no missing links." On the contrary, 
man's pedigree is almost all " missing links." Of late much 
interest has been aroused by Dubois' discovery of Pithecanthropus 
erectus in the supposed Pliocene of Java, and great controversy 
has arisen over the significance of this remarkable fossil. Some 
authorities regard it as a low type of man, others as an unusually 
large anthropoid ape, and others, again, as a connecting link 
between the two. The fact is that the known remains are too 
fragmentary for a definite judgment, and it is greatly to be hoped 
that the expeditions now projected, or on the way, may succeed in 
gathering material for a clear answer to the most profoundly 
interesting and important of all biological questions, the descent 
of man. 
This paper has already grown to an unmerciful length, and 
(1) Handbuch der Palaontologie, Bd. iv. pp. 713-4. 
