which Mr. Flower,
Conservator of the Museum of the Royal College of Surgeons, was good
enough to dissect for me; the latter, from the photograph of a similarly
dissected Chimpanzee's brain, given in Mr. Marshall's paper above
referred to. 'a', posterior lobe; 'b', lateral ventricle; 'c', posterior
cornu; 'x', the hippocampus minor.)

In fact, all the abundant and trustworthy evidence (consisting of the
results of careful investigations directed to the determination of these
very questions, by skilled anatomists) which we now possess, leads
to the conviction that, so far from the posterior lobe, the posterior
cornu, and the hippocampus minor, being structures peculiar to and
characteristic of man, as they have been over and over again asserted
to be, even after the publication of the clearest demonstration of the
reverse, it is precisely these structures which are the most marked
cerebral characters common to man with the apes. They are among the most
distinctly Simian peculiarities which the human organism exhibits.

As to the convolutions, the brains of the apes exhibit every stage of
progress, from the almost smooth brain of the Marmoset, to the Orang
and the Chimpanzee, which fall but little below Man. And it is most
remarkable that, as soon as all the principal sulci appear, the pattern
according to which they are arranged is identical with that of the
corresponding sulci of man. The surface of the brain of a monkey
exhibits a sort of skeleton map of man's, and in the man-like apes
the details become more and more filled in, until it is only in minor
characters, such as the greater excavation of the anterior lobes, the
constant presence of fissures usually absent in man, and the different
disposition and proportions of some convolutions, that the Chimpanzee's
or the Orang's brain can be structurally distinguished from Man's.

So far as cerebral structure goes, therefore, it is clear that Man
differs less from the Chimpanzee or the Orang, than these do even
from the Monkeys, and that the difference between the brains of the
Chimpanzee and of Man is almost insignificant, when compared with that
between the Chimpanzee brain and that of a Lemur.

It must not be overlooked, however, that there is a very striking
difference in absolute mass and weight between the lowest human
brain and that of the highest ape--a difference which is all the more
remarkable when we recollect that a full grown Gorilla is probably
pretty