834 MAN 



brains. The intcrcoUicular sulcus between the superior colliculi is broader and 

 deeper than in the anthropoids. It forms a larger pineal fossa for the epiphysis 

 cerebri. The function attributed to the epiphysis in inhibiting growth and 



FIG. 356. MAN. LE\ EL OF THE OPTIC CHIASM. 

 CEN, Central Gray Matter; cm, Mammillary Body; cp, Cerebral Peduncle; Cph, Corpus Hypothalamicum; 

 CFT, Central Tegmental Tract; lcb. Lateral Geniculate Body; mgb, Mesial Geniculate Body; nru. Nucleus 

 Ruber; op.x. Optic C^^hiasm; pul, Pulvinar; ref. Reticular Formation; sbn. Substantia Nigra; sc, Superior 

 Colliculus; STR, Striatorubral Tract. (Accession Man. Section gSo. Actual Size 65 X 35 mm.) 



retarding sexual development is significant in that it delays maturity in man 

 to a much later period than in other mammals. 



LEVEL OF THE OPTIC CHLASM (FIGS. 355, 356) 



At this level the contour of the section shows the characteristic modifi- 

 cations of transition from the midbrain to the inlerhrain. The third ventri- 

 cle ( V3) appears as a deej:) narrow cleft between the two nuclear structures 



