256 ZOOTOMY. 



339. The cerebellum (Fig. 58, cb), a median, laterally- 

 compressed, crest-like mass, lying above the anterior part of 

 the medulla oblongata ; it is marked by transverse furrows or 

 sulci, between which are elevations or gyri : on the lateral 

 surfaces of the cerebellum the sulci and gyri radiate from 

 an area on which is a slight elevation, the flocculus (/) : 

 the cerebellum has a pink tint in the fresh brain, being 

 composed externally of grey matter. 



340. The optic lobes {o.P), paired, white, ovoidal bodies, 

 situated one on either side, immediately in front of the 

 medulla and below the cerebellum. 



341. The cerebral hemispheres {c.h), paired, obtusely 

 conical bodies, in close contact with one another, and 

 situated immediately in front of the cerebellum and optic 

 lobes, with both of which their hinder surfaces are in contact : 

 they consist externally of grey matter. 



342. The pineal body (/«), a small rounded mass on 

 the dorsal surface of the brain, wedged in between the 

 cerebral hemispheres and the cerebellum. 



343. The olfactory lobes {olf), small blunt projections, 

 connected one with the anterior end or apex of each 

 cerebral hemisphere : from them the olfactory nerves 

 (first pair of cerebral nerves) are given off" to the nasal sacs." 



344. The optic tracts (o.t), forming a broad, white 

 transverse band, concave forwards, between the optic lobes, 

 on the lower surface of the brain : from their anterior 

 median region the optic (second) nerves (11) spring. 



345. The infundibulum {inf), a rounded area with 

 a central aperture, just posterior to the optic tracts: to 

 it is attached the pituitary body, which is usually 

 detached in removing the brain from the skull. 



346. The third nerve (in), arising close behind the 

 infundibulum, a short distance from the middle line, from a 



