PEDIGREE OF THE APES, 273 
teeth, of which two are pre-molars and three molars, 
altogether thirty-two teeth. But all Apes of the New 
World, all Platyrrhini, have four more cheek teeth, namely, 
three pre-molars and three molars on each side, above and 
below: they consequently possess thirty-six teeth. Only 
one small group forms an exception to this rule, namely, 
the Arctopitheci, or Clawed Ayes, in whom the third molar 
has degenerated, and they accordingly have on each half of 
their jaw three pre-molars and two molars. They also 
differ from the other Platyrrhini by having claws on the 
fingers of their hands and the toes of their feet, not nails 
like Man and the other Apes. This small group of South 
American Apes, which includes among others the well- 
known pretty little Midas-monkey and the Jacchus, must 
probably be considered only as a peculiarly developed 
lateral branch of the Platyrrhini. 
Now, if we ask what evidence can be drawn, as to the 
pedigree of Apes, from the above facts, we must con- 
clude that all the Apes of the New World have developed 
out of one tribe, for they all possess the characteristic jaw 
and the nasal formation of the Platyrrhini In like 
manner it follows that all the Apes of the Old World must 
be derived from one and the same common primary form, 
which possessed the same formation of nose and jaw as 
all the still living Catarrhini. Further, it can scarcely 
be doubted that the Apes of the New World, taken as an 
entire tribe, are either derived from those of the Old World, 
or (to express it more vaguely and cautiously) both are 
diverging branches of one and the same tribe of Apes. We 
also arrive at the exceedingly important conclusion— 
which is of the utmost significance in regard to Man’s dis- 
