MONOTONY OF ANTHROPOIDEA 
and not so much as contrasting with the lower lying 
Lemuroidea. It isa noteworthy fact about the monkey 
tribe that, numerous and widespread as are its repre- 
sentatives, there are but slight variations from one easily 
definable type. There is no creature belonging to this 
assemblage that is not at once referable to its proper 
place in the system by the least experienced of those 
accustomed to observe. 
The singularly monotonous type of structure preva- 
lent in the Anthropoidea contrasts with the diversity 
shown by the Carnivora, the Ungulata, the Rodentia, 
the Marsupials, and indeed nearly all the orders and 
groups of the mammalia, including even the lemurs, 
the second sub-order of the Primates. This may be 
associated with an equal uniformity in way of life. 
Monkeys are essentially a climbing race, and are vege- 
tarians tempered by slightly carnivorous habits. It 
may also be associated with a high position in the series 
of mammals. Those orders which come nearer to the 
base of the series, which are, therefore, nearer to the 
primitive mammal, have clearly greater capacities for 
variation than the thinnest topmost twigs of the 
mammalian tree of life, whose characters are, therefore, 
more fixed. This suggestion may be both checked and - 
enforced by the consideration that monkeys are a 
modern race, and that, may be, they have not yet had 
time to throw out feelers in various directions, some 
destined to produce a new race of descendants, others 
more comparable to sterile side branches. Uniform 
though the internal as well as external anatomy of the 
monkey tribe is, it is yet possible to sort them out into 
three divisions, which can be detected by internal as 
well as external characters, or sometimes by the former 
only. 
Broadly speaking, the mammalian inhabitants of 
South America differ from much their nearest allies 
22 
