ON THE BRAINS OE TWO IDIOTS OF EUROPEAN DESCENT. 
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Table II. — Eatios between the Dimensions of different parts of the Encephalon, in the 
European, in the Bushwoman, in the two Idiots, and in the Chimpanzee. 
Explanation of the Plates. 
With the exception of figures 7, 8, and 20, which are taken from Gratiolet, and of 
figure 23, which is merely a tracing from nature, the illustrations to this paper have 
been lithographed from Mr. Herbert Watkins’s photographs, aided by reference to the 
objects themselves. All the figures agree in size with the preserved brains, excepting 
figure 9, which, as well as figures 7 and 8, taken from Gratiolet, is reduced to three- 
fourths of the proper linear dimensions. The references to the cerebral convolutions 
are alike in all the Plates; and a common explanation of these is appended to the 
general description. Eeferences to a few other details are given under each Plate. 
PLATE XVII. 
Fig. 1. Upper surface of the preserved brain of the Bushwoman. 
Fig. 2. Base of the same brain : o, olfactory nerve ; a, corpora albicantia. 
PLATE XVIII. 
Fig. 3. Left side of the same brain. 
Fig. 4. Vertical median section of the same brain, showing the inner surface of the left 
hemisphere of the cerebrum, with the cut surfaces of the cerebral peduncle, 
the corpus callosum, the cerebellum, ponsVarolii (p), medulla oblongata, and 
other parts : a, anterior commissure ; q, corpora quadrigemina. 
* These ratios are calculated from measurements taken on .the intracranial cast ; the rest of the ratios, in 
the case of the idiot boy, are taken from measurements of the preserved brain. 
