ON THE BRAINS OF TWO IDIOTS OF EUROPEAN DESCENT. 
517 
peduncle (Plate XIX. fig. 5), by a narrow ridge (*), with the middle internal or unci- 
nate convolution (19) of the temporal lobe. The callosal convolution is large, and its 
crested upper border is well marked posteriorly. The marginal convolution is relatively 
rather harrow, and its secondary convolutions are simple. Altogether these internal con- 
volutions are less complex than in the European. 
The quadrilateral lobule (Plates XVIII. & XIX. figs. 4 & 5, is/) (lobule quadrilatere, 
Foville; quadrate lobe, H.), the extension backwards and upwards of the callosal 
convolution, is very well marked ; but it is short, and, in accordance with the more 
upright direction of the internal perpendicular fissure (already described), is not quite so 
much inclined backwards as in the European. It is smoother and narrower above than 
below, instead of being wider than, or of equal width as, in the European — a condition 
which coincides with the backward extension of the ascending parietal convolutions and 
the fissure of Kolando. 
Of the three internal temporal convolutions (Plate XIX. fig. 5), the upper one, con- 
cealed in the dentate fissure, m, and corresponding with the corps godronne of authors 
(the dentate convolution, H.), is present, but very small, the fascia dentata being only 
just recognizable. The middle internal temporal convolution (19-19) (pli temporal moyen 
interieur, Gb. ; uncinate, H.), continuous upwards by the narrow ridge (*) with the 
convolution of the corpus callosum, and ending forwards in the unciform lobule (w) 
(lobule de l’hippocampe, Gb. ; and crochet of Vicq d’Azyb), is relatively narrow and less 
prominent in the Bushwoman’s brain, the crochet being particularly small. The lower 
temporal convolution (9-9), which in fact is the same as the lower external temporal, and 
is marked off from the middle one by the parallel fissure of Geatiolet (n-n) (collateral 
fissure, H.), is very broad, though smooth. The secondary sulci of these convolutions 
are chiefly longitudinal, and more simple than in the European brain. The middle con- 
volution (19), that above the collateral fissure, is traceable round the very tip of the 
occipital lobe, and, curving upwards on its hinder aspect, joins the middle and lower 
occipital convolution; the lower one (9) unites more directly with the lower occipital 
row. 
The bottom of the calcarine portion (l—l) of the fissure of the hippocampi corresponds 
with the hippocampus minor in the posterior horn of the lateral ventricle. Deeply 
seated between its two short branches behind is a ridge of cerebral substance, repre- 
sentative of the calcarine lobule of Flowee. 
The triangular occipital lobule (Plates XVIII. & XIX. figs. 4 & 5, 25-25) (lobule occipital, 
Gb.) is of small size, and has its anterior and inferior margins more even, and its surface 
less complex than in the European brain. Owing to the less inclined position of the 
internal perpendicular fissure, this lobule approaches somewhat nearer to the vertex 
than is customary. 
Lastly, the lower internal connecting convolution (Plate XIX. fig. 5) (pli de passage 
inferieur interne, Gb.) which joins the lower and anterior angle of the occipital lobule 
with the adjacent part of the quadrate lobule, is represented, as usual, by a ridge con - 
mdccclxiv. 3 z 
