458 PHYSIOLOGICAL SERIES. 



divided into flocculus and paraflocculus in such a manner 

 that the former completely overlaps the latter, although in 

 this case the two lobules are of approximately the same 

 size. 0. C. 1338 1 6. 



D. 671. The brain of a Chimpanzee (Anthropopithems troglo- 

 dytes) . 



In spite of the fact that this excellently preserved spe- 

 cimen has been badly injured by saw-cuts in the occipital 

 region, it has been mounted because of the interest attach- 

 ing to its insular and occipital regions. 



The remarks made concerning the insulao of the last 

 specimen apply to the corresponding regions of the two 

 respective hemispheres of this specimen. But the chief 

 interest here is the instructive demonstration of opercular 

 formation. The dorsal operculum of the anterior insular 

 area is being formed in spite of the fact that the superior 

 limiting sulcus is incomplete. This is especially well 

 shown on the left side. 



The marked dwindling of the mesial extremity of the 

 occipital operculum forms a most pronounced contrast to 

 the condition met with in all the other Chimpanzee's 

 brains in this Collection. It shows that we cannot rely in 

 every case upon this character to distinguish a Chimpanzee 

 from a Gorilla or even an Orang (cfr. specimen D. 649). 



The floccular lobe is very interesting. The paraflocculus 

 and flocculus being clearly distinguished not only by 

 position but also by shape in a manner quite unusual in 

 the Anthropoid Apes. Presented by Prof. J. Marshall. 



D. 672. The brain of a Chimpanzee (Anthropopithecus troglo- 

 dytes). 



A considerable part of the right cerebral hemisphere lias 

 been removal \\\ dissection in order to expose the whole 

 insula ; and the left licmi-j.lien' lias been cut horizontally 

 in order to show the relationship of the insula to the 

 claustrum and the lenticular nucleus. This section has 

 been made in order that it may be compared with specimen 

 D. 728, which is a corresponding section of the human 

 brain. 



