436 PHYSIOLOGICAL SERIES. 



during preservation. This enables us to see at a glance the 

 real -condition of the various sulci, and not merely the 

 surface-pattern. 



Tlio floccular lobes are very small, as in D. 648, and 

 practically reduced to flocculus (sensu stricto), as in the 

 human brain. On the mesial aspect of the right hemi- 

 sphere the septum lucidum and f'ornix of the left side arc 

 displayed, and in that portion of the section just above the 

 mammillary bodies is seen a white ascending streak, which 

 is the mammillo-thalamic tract (Vicq d'AzyrY). In the 

 section of the cms the substantia nigra is clearly seen. On 

 the mesial aspect of the left hemisphere, the head of the 

 nucleus caudatus is seen bulging into the anterior cornu of 

 the lateral ventricle. The gaping sulci afford an exceptional 

 opportunity of studying the true relations of these im- 

 portant features of the brain. 



The submerged posterior part of the insula is visible, 

 and its relation to the uncovered anterior part (which is 

 partly mapped out by the fron to-orbital and superior 

 limiting sulci) is clearly demonstrated. The relation of the 

 inferior transverse sulcus of Eberstaller .to the Sylvian 

 fissure is admirably shown. 



There is a simple and easily-understood grouping of the 

 inferior precentral (arcuate), inferior frontal (" rectus "), 

 superior precentral (vide right hemisphere), and superior 

 and middle frontal sulci. 



There is a typical intraparietal sulcus. The occipital 

 region is disposed as in the last specimen. The small 

 inferior occipital sulcus is fused to the lower end of the 

 Simian sulcus. But it is functionally represented by a 

 deep occipito-temporal sulcus, the anterior end of which is 

 joined to the posterior element of the inferior (middle) 

 temporal series. 



The collateral sulcus is represented by two parallel 

 furrows. 



D. 651. The brain of an ()nmg-< Mitang (.S'/wm *////r//.v). Tin- 

 left hemisphere has been separated. 



The irregular pattern formed by the sulci in the left 

 frontal area is o.-ent ially identical with that of -p.vimrn 



