the structure of the brain, does not admit the existence of this
sub-group, and no doubt it is a broken one. Thus the orang, as Mr. St.
G. Mivart remarks, is one of the most peculiar and aberrant forms to
be found in the Order. (13. Transactions, Zoolog. Soc. vol. vi.
1867, p. 214.) The remaining non-anthropomorphous Old World monkeys,
are again divided by some naturalists into two or three smaller
sub-groups; the genus Semnopithecus, with its peculiar sacculated
stomach, being the type of one sub-group. But it appears from M.
Gaudry s wonderful discoveries in Attica, that during the Miocene
period a form existed there, which connected Semnopithecus and Macacus;
and this probably illustrates the manner in which the other and higher
groups were once blended together.
If the anthropomorphous apes be admitted to form a natural sub-group,
then as man agrees with them, not only in all those characters which he
possesses in common with the whole Catarrhine group, but in other
peculiar characters, such as the absence of a tail and of callosities,
and in general appearance, we may infer that some ancient member of the
anthropomorphous sub-group gave birth to man. It is not probable that,
through the law of analogous variation, a member of one of the other
lower sub-groups should have given rise to a man-like creature,
resembling the higher anthropomorphous apes in so many respects. No
doubt man, in comparison with most of his allies, has undergone an
extraordinary amount of modification, chiefly in consequence of the
great development of his brain and his erect position; nevertheless, we
should bear in mind that he is but one of several exceptional forms of
Primates. (14. Mr. St. G. Mivart, Transactions of the Philosophical
Society, 1867, p. 410.)
Every naturalist, who believes in the principle of evolution, will
grant that the two main divisions of the Simiadae, namely the
Catarrhine and Platyrrhine monkeys, with their sub-groups, have all
proceeded from some one extremely ancient progenitor. The early
descendants of this progenitor, before they had diverged to any
considerable extent from each other, would still have formed a single
natural group; but some of the species or incipient genera would have
already begun to indicate by their diverging characters the future
distinctive marks of the Catarrhine and Platyrrhine divisions. Hence
the members of this supposed ancient group would not have been so
uniform in their dentition, or in the structure of their nostrils, as
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