516 
PROFESSOR TIEDEMANN ON THE BRAIN OF THE NEGRO. 
entirely, and project considerably over it. The whole external surface of the hemi- 
spheres is covered by a great number of g-yri, separated by deep sulci. The gyri are 
particularly large on tbe anterior part of the hemispheres of the brain of the Bosjes 
woman. It is remarkable that the gyri and sulci of the hemispheres show more 
symmetry than is usually found in European brains. This is particularly visible in the 
brain of the Bosjes woman. On the middle of the basis of the brain (Plate XXXII.) 
are the pons Varolii, nodus encephali, or tuber annulare, the crura or pedunculi of 
the cerebrum, the eminentise candicantes or corpora albicantia, the gray tubercu- 
lum, and the hypophysis cerebri, or the glandula pituitaria, which on the whole are 
very much the same, as in the European brain. The pedunculus of the hypophysis 
in the brain of the Negro Honore' (e. Plate XXXIII.) was somewhat thicker and 
larger than in the European. The hypophysis cerebri {f. Plate XXXIII.) was some- 
what smaller. I cannot say whether this is always the case in the brain of the Negro. 
In reference to the internal structure of the brain of the Negro, it is composed, 
like the brain of the European, of two substances, the outer gray, or cortical sub- 
stance, and the internal white fibrous or medullary substance, as has been observed 
by several anatomists ; but they do not agree on this point. 
J. F. Meckel* * * § says the gray substance is of a darker colour than in the European 
brain, and also the medullary substance is not so white, but yellowish gray or light 
brown. 
J. G. Walter^ found the medullary substance in the Negro just as white as in 
the European : the cortical substance, on the other hand, darker, of a grayish brown 
colour, which he attributed to the darker colour of the blood in the Negro. Camper, 
Bonn ;£, and Soemmerring § found likewise the medullary substance just as white in 
the Negro as in the European. 
Soemmerring says that he examined three perfectly fresh Negro brains without 
finding any difference in the colour of the cortical substance from that of the Euro- 
pean. Fl. Caldani||, on the contrary, found the gray substance in the brains of two 
Negroes darker than in Europeans. Rudolphi has remarked the same in the brain 
of a Mulatto. I can say nothing regarding the colour of the medullary and cortical 
* De la Diversite de Couleur dans la Substance Medullaire de Negres ; Histoire de l’Academie de Berlin, 
1753, p. 97. Du Cerveau des Negres, ibid., 1757, p. 69. 
f Epistola Anatomica ad virum illustrem W. Hunterum de Venis Oculi, p. 20. Berolini, 1778. “In 
yEthiope meo dissecto color omnium partium medullarium cerebri, cerebelli et medullse oblongatae erat perfecte 
albus. Substantia vero corticalis cerebri, quae in Europeeis cineritii coloris est, in hoc AEthiope paulo obscu- 
rioris, hoc est ex cineritio bruni coloris est. Hsec permutatio coloris mihi oriri videtur a sanguine, qui ad sub- 
stantiam corticalem fertur.” 
X Descriptio Thesauri Ossium morbosorum Hoviani, p. 133. “ Medulla cerebri, oblongata atque spinalis 
^Ethiopissse intus albissima erat.” 
§ Vom Korperlichen Unterschied des Negers, S. 18. 
|| Congettura sopra Uso della glandola Timo, con alcuni altri Discorsi, p. 38. Venezia, 1808. 
Lehrbuch der Physiologie, B. ii. Abth. 1. S. 15. 
