ROLLESTON ON THE BRAIN OF THE ORANO UTi.NO. 



209 



Iu Orang = 1^ inch. : 3 inch. = 1 : 2-40. 



In Man = lj inch. : 41 inch. = 1 : 275. 



In Chimpanzee* = 15-5'" : 325'" = 0"48 : 1. 



In Orang = 4^ inch. : 1|. inch. = 1 : 944. 



/ { In Man = 6 - 7 in. : 3 - 4 in. = 1 : 0-50, or 1 : 42. 



In Chimpanzeef = 99 mil. : 43 mil. = 1 : 043. 



The following six measurements of height, breadth, and length of 

 the human cerebral hemispheres, are the three maximum and the three 

 minimum measurements given by Husche, at the ninety-ninth page of 

 his work, already referred to. 



Maximum height in Chinese = 155 mil. 

 ,, breadth in Inca = 1733 ,, 

 „ length iu Croat =200 „ 



Minimum in Hiudoo Fakir =124 mil. 

 „ Croat = 103 „ 



Inca =151 „ 



From these measurements, it is evident that the variations of height 

 oscillate within narrower limits in the human brain than the variations 

 either of length or of breadth. The measurement of height, therefore, 

 would seem to possess greater serial importance than either of the other 

 two measurements. Yet the following measurements will show that it 

 is precisely in this dimension that the brain of the apes stands in the 

 greatest relative inferiority to that of man. 



Length of hemispheres in Orang : length in Man 

 „ Chimpanzee : ,, 



4^ in. 



99 in. 



Breadth of ditto in Orang 

 ,, Chimpanzee 



breadth in Man = 3^ in. 

 ,, = 95 m.% 



= 87m.§ 



6-7in. = 1 

 6- 7 in. = 1 



4-7 in. = 1 

 4-7m. = 1 

 4-7m. = 1 



1-4 or 1 



1-54 or 1 



1-64. 

 1-79. 



1-23 or 1 : 215. 

 1-08 or 1 : 1-88. 

 1-17 or 1 : 2-06. 



Height of ditto in Orang : height in Man = 2^ in. : 5 = 1 : 2*35. 



„ Chimpanzee : ,, = 54m. J : 5 = 1 : 2*38. 



= 64m.§:5 =1-2. 



Of all the differences of measurements and their relations as yet ad- 

 duced, the difference between the relative heights of the human and the 

 simious brains seems the most important. 



Small as the difference in the two measurements of corpora callosa 

 may seem, we must yet record that posteriorly to the posterior bourrelet 

 or rounded edge of that body in the orang, the corpora quadrigemina 

 came into view when the brain was removed from the skull. This ob- 

 servation will be seen later to have, when coupled with certain others, 

 considerable value, as showing the greater relative shortness of the cor- 

 pus callosum. It was noticeable that the anterior pair of corpora quadri- 

 gemina were less sharply marked off from the posterior than in man. 



The central notch of the cerebellum was much shallower relatively 



* Schrceder van der Kolk ? citt. Huschke, 1 c, 

 X Schroedev van der Kolk ap. Huschke, p. 129. 

 VOL. I. — N. H. R. 2 E 



p. 82. 



f Idem, Ibid., p. 129. 



§ Gratiolet, Memoire, p. 54. 



