erior cornu,
wherein only a stripe is visible as an indication of the hippocampus
minor;' yet the Figure 4, in their second Plate, shows that this
posterior cornu is a perfectly distinct and unmistakeable structure,
quite as large as it often is in Man. It is the more remarkable that
Professor Owen should have overlooked the explicit statement and figure
of these authors, as it is quite obvious, on comparison of the figures,
that his woodcut of the brain of a Chimpanzee (l. c. p. 19) is a reduced
copy of the second figure of Messrs. Schroeder van der Kolk and Vrolik's
first Plate.

"As M. Gratiolet (l. c. p. 18), however is careful to remark,
'unfortunately the brain which they have taken as a model was greatly
altered (profondement affaisse), whence the general form of the brain
is given in these plates in a manner which is altogether incorrect.'
Indeed, it is perfectly obvious, from a comparison of a section of the
skull of the Chimpanzee with these figures, that such is the case; and
it is greatly to be regretted that so inadequate a figure should have
been taken as a typical representation of the Chimpanzee's brain."

From this time forth, the untenability of his position might have been
as apparent to Professor Owen as it was to every one else; but, so far
from retracting the grave errors into which he had fallen, Professor
Owen has persisted in and reiterated them; first, in a lecture delivered
before the Royal Institution on the 19th of March, 1861, which is
admitted to have been accurately reproduced in the 'Athenaeum' for the
23rd of the same month, in a letter addressed by Professor Owen to that
journal on the 30th of March. The 'Athenaeum report was accompanied by
a diagram purporting to represent a Gorilla's brain, but in reality so
extraordinary a misrepresentation, that Professor Owen substantially,
though not explicitly, withdraws it in the letter in question. In
amending this error, however, Professor Owen fell into another of
much graver import, as his communication concludes with the following
paragraph: "For the true proportion in which the cerebrum covers the
cerebellum in the highest Apes, reference should be made to the figure
of the undissected brain of the Chimpanzee in my 'Reade's Lecture on the
Classification, etc., of the Mammalia', p. 25, Figure 7, 8 vo. 1859."

It would not be credible, if it were not unfortunately true, that this
figure, to which the trusting public is referred, without a