KOLLESTOX ON THE BRAIN OF THE 0KANG UTANG. 205 



figures of the brains of the Simia Rhesus, Simla Nemestrina, Simia 

 Sabceus, and Cebus Capucinus. If the weight of this latter mass of 

 evidence is not sufficient to make us consider the relations of the parts 

 as seen in our specimen, fig. 2, as mere individual peculiarities, it is at 

 all events sufficient to justify us in denying them, not merely all classi- 

 ficatory, bat also all physiological value. 



For arrogating importance to any projection or predominance back- 

 ward of the cerebellum, still less justification exists. For so doing no 

 other colour can be brought forward than such as our own figures can 

 afford, for which we have adduced a sufficient explanation — or such as 

 certain confessedly imperfect figures,* taken as they were from a con- 

 fessedly badly preserved brain, may be thought to furnish, when weighed 

 against the all but unanimous verdict to the contrary, which is obtained by 

 the examination of authentic representations, and of well-preserved speci- 

 mens. In every specimen, save the single one the subject of this pa- 

 per, of a simious brain above the grade of a lemur, contained in our 

 Museum, the cerebellum is as much covered posteriorly by the cerebral 

 lobes as we have already shown it to be laterally. The same remarks 

 apply to every one of M. Gratiolet's own figures j the only exceptions to 

 the rule which his plates offer being those which the imperfect figures of 

 Tyson and Sandifort furnish. Tiedemann's Icones of the lower apes are 

 unanimous on the same side, but the figures which he gives of the brains 

 of the orang and chimpanzee, in his work on the Brain of the Negro, f 

 represent the cerebellum uncovered, on both sides, to a somewhat 

 greater extent than it is in our figures 3 and 4, on one sidej. 



A careful study, however, of our figures, coupled with an examina- 

 tion of the skulls of several anthropoid apes, will lead to the belief that 

 the cerebral hemispheres of the apes bulge less laterally than do those of 

 man ; that they are not merely more boat-shaped, and tapering anteriorly 

 and posteriorly, but that they are more wall-sided, and less protuberant 

 laterally. 



Though we may be inclined to consider the diminution in lateral 

 expanse, and in backward growth of the posterior lobes, D, of which 



* Schrceder van der Kolk et Vrolik, citt. Gratiolet, Mem. p. 49, Planch vi. 5 and 6. 



f Citt. ap. "Wagner's Icones Zootomies Taf. viii., figs. 2 and 3. 



j Since the above paragraphs were -written, casts have been taken of the interior of the 

 skulls of our second orang and of the chimpanzee with the following results. The cast of 

 the orang's skull approximates more nearly to the proportions of the brain we have figured 

 than does the prepared brain it represents ; the relative extent of the space occupied by the 

 mass corresponding to the cerebellum, being somewhat greater than that occupied by the 

 cerebellum itself, in the specimen. Still, in such a view of the cast as that given in fig. 3 of 

 the first of our brains, no cerebellar surface at all comes into view ; though a little less 

 cerebral surface comes out laterally than in the preserved brain in a similar view to that 

 in fig. 2. The cast of the chimpanzee's skull represents the cerebral hemispheres as 

 overlapping the cerebellum to a greater extent, posteriorly, than they do in the prepara- 

 tion, the hemispheres having in this, as in certain figured preparations, fallen apart late- 

 rally somewhat, and lost thus in antero- posterior, what they have gained in lateral, extent. 



