OiST THE BRAINS OP TWO IDIOTS OP EUROPEAN DESCENT. 
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internal convolution (mi) bounding the olfactory sulcus, and an external curved convolu- 
tion (mu) forming the outer border of the frontal lobe, consists of three short simple 
curved branches, very like those found in the Ape, instead of the tortuous sulci seen 
in the European brain. The forms of the surrounding orbital convolutions themselves, 
including the proper supraorbital (u), are so broad and simple, that their subordinate 
divisions, which are so complex in the European brain, can hardly be said to exist. 
The frontal convolutions (Plates XVII. & XVIII. figs. 1 & 3) are, as usual, arranged 
in three stages or rows, separated from each other by two deep secondary sulci. The 
lower row (i-i) (le premier etage, Gratiolet ; infero-frontal, Huxley) is well defined, 
and intermediate in complexity between its condition in the Hottentot Venus and an 
average European brain. The middle row (2-2 r) (le second etage, Gr. ; medio-frontal, H.) 
resembles, in its simplicity of form and detail, that of the Hottentot Venus much more 
than that of the European brain, especially as seen from above. Posteriorly (2 1) it 
joins the upper end of the first ascending parietal convolution (4), as in the Hottentot 
Venus, whilst in the European the continuity is usually interrupted by a secondary 
sulcus ; but instead of being continuous, as in the former, in front of the Sylvian fissure, 
with the lower frontal, it is there separated from it, as in the latter. The upper row (3 -31) 
of frontal convolutions (le troisieme etage, Gr. ; supero-frontal, H.), in its proportion to 
the other two rows and its subordinate divisions, approaches nearer to the European 
type ; but it is simpler, and in the upper view (Plate XVII. fig. 1) much narrower, 
narrower even than those figured in the Hottentot Venus. As usual, it joins ( 3 /) the first 
ascending parietal convolution ( 4 1), behind and above, in front of the fissure of Rolando. 
Along the border of the longitudinal fissure, where it is blended with the great marginal 
convolution, it is less frequently notched than in the European brain ; so that one par- 
ticular notch (in front of 31) becomes very evident. In this respect the resemblance is 
very close to the Hottentot- Venus brain; but the left notch is further back than the 
right, instead of the reverse. In the European brain these notches are symmetrically 
placed on the two sides (see Plate XX.). 
The first , or anterior ascending parietal convolution (Plates XVII. & XVIII. figs. 
1 & 3, 4-4/) (premier pli ascendant, Gr. ; antero-parietal, H.) is larger and more pro- 
nounced in its form than in the Hottentot Venus ; in its general mass it approaches the 
European character; but it has fewer secondary sulci, and, as already stated, joins 
anomalously the middle frontal row. It is broader on the right side than on the left. 
As usual, it forms the anterior border of the fissure of Rolando, joins at its lower end 
the supramarginal convolution ( 4 /r — 5 //) which limits that fissure below, and at its upper 
end runs forwards into the upper row of frontal convolutions, and backwards around 
the upper end of the fissure of Rolando into the second or posterior ascending parietal 
convolution (5). In the brain of the Hottentot Venus (see Plate XX.), this last-named 
connexion is almost concealed within the longitudinal fissure ; whereas in the European 
brain it is superficial, owing to the greater upward development of this part of the brain. 
In the former case the hinder end of the fissure of Rolando loses itself in the longitudinal 
