Page:Geological Evidences of the Antiquity of Man.djvu/509

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CHAP. XXIV.
OF MAN AND APES COMPARED.
489

the presence of both the hippocampus minor and the posterior cornu.

Tiedemann had expressly stated that 'the third or hinder lobe in the ape covered the cerebellum as in Man,'[1] and as to his negative evidence in respect to the internal structure of that lobe, it can have no weight whatever against the positive proofs obtained to the contrary by a host of able observers. Even before Tiedemann's work was published, Kuhl had dissected, in 1820, the brain of the spider-monkey (Ateles beelzebuth), and had given a figure of a long posterior cornu to the lateral ventricle, which he had described as such.[2]

The general results arrived at by the English anatomists already cited, and by Professor Rolleston in various papers on the same subject, have thus been briefly stated by Professor Huxley:—

'Every lemur which has yet been examined has its cerebellum partially uncovered, its posterior lobe with the contained posterior cornu and hippocampus minor more or less rudimentary. Every marmoset, American monkey, Old World monkey, baboon or man-like ape, on the contrary, has its cerebellum entirely covered, a large posterior cornu, and a well-developed hippocampus minor.

'In many of these creatures, such as the Saimiri (Chrysothrix), the cerebral lobes overlap and extend much farther behind the cerebellum in proportion than they do in Man.'[3]

It is by no means pretended that these conclusions of British observers as to the affinity in cerebral structure of Man and the Primates, are new, but, on the contrary, that they confirm the inductions previously made by the principal continental teachers of the last and present generations, such

  1. Tiedemann, Icones cerebri Simiarum, &c., p. 48.
  2. Beiträge zur Zoologie, &c., Frankfurt am Main, 1820.
  3. Huxley.