HUXXET ON THE RELATIONS OF MAN TO THE LOWEB. ANIMALS. 83 



conies slowly effaced with age, and in the adult it has completely disappeared. The brain 

 of the Hottentot Venus is, then, in all respects, inferior to that of white men arrived at the 

 normal term of their development. It can be compared only with the brain of a white 

 who is idiotic from an arrest of cerebral development." — p. 66. 



Finally, with respect to the fourth difference, Tiedemann observes 

 (p. 515) of the negro's brain: — 



" The anterior part of the hemispheres is something narrower than is usually the case 

 in Europeans. This is particularly remarkable in the brain of the Bosjes woman." 



Thus, the cerebral hemispheres of the Bosjesman (and to a certain 

 extent of the negro), so far as the evidence before us goes, are diffe- 

 rent from those of the white man ; and the circumstances in which they 

 differ — viz., the more pointed shape of the cerebral hemispheres, the 

 greater symmetry of their convolutions, and the different development 

 of certain of these convolutions, — are all of the same nature as most of 

 those which distinguish the ape's brain from that of man. In other words, 

 if we place A, the European brain, B, the Bosjesman brain, and C, the 

 orang brain, in a series, the differences between A and B, so far as they 

 have been ascertained, are of the same nature as the chief of those be- 

 tween B and C. 



The brains of the lowest races of mankind have been hardly at all 

 examined ; and it would be a matter of great interest to ascertain whe- 

 ther, in these races, there is any trace of the external perpendicular 

 fissure, any diminution of the lobule of the marginal convolution, and 

 any increase of the proportional size of the nerves to the cerebral mass. 

 Medical men living at the Cape of Good Hope, in Australia, and within 

 reach of the Hill-men of India, will, it is to be hoped, some day solve 

 these problems for the zoologist. 



Let it be admitted, however, that the brain of man is absolutely 

 distinguished from that of the highest known apes — ■■ 



1st. By its large size, as compared with the cerebral nerves ; 



2nd. By the existence of the lobule of the marginal convolution ;* 



3rd. By the absence of the external perpendicular fissure — 

 And then let us turn to the other side of the argument, and weigh 

 these differences against those which separate the brains of PWiecus or 

 Troglodytes from those of the lowest Quadrumana. 



The brain of Lemur mongos is well figured, and constantly referred 

 to by Tiedemann in the " Icones" so often referred to. The few gyri ; 

 the shortness of the cerebral hemispheres, in the region of the third 

 lobe, which leave fully half the cerebellum uncovered ; the large size 

 of the vermis superior ; the prominence of its flocculus ; the great size 

 of the olfactory nerves, which rather deserve the name of olfactory 

 lobes ; the singleness of the corpora candicantia ; the comparatively 

 small and flat pons varolii ; the presence of corpora trapezoidea ; and, in 



* The second and third differences are mentioned by Gratiolet, to whose Memoir I 

 must refer for a statement of their nature. 



