158 



ZOOLOGY 



SECT. 



capsule. The diencephalon (ZH) is comparatively small ; its roof 

 is very thin, while the floor is composed of two thickish masses 



L ; ol Tro VII Gp IV HE 

 ZH Mil 



FIG. 821. Brain of Scyllium canicula. A, dorsal view ; B, ventral view ; C, lateral view. 

 F. rfio. fossa rhoinboidalis (fourth ventricle) ; Gj>, epiphysis ; ////, cerebellum ; HS. H, hypo- 

 physis ; L. ol. olfactory bulb ; Mff, mid-brain ; Ntf, medulla oblougata ; Sr, saccus vasculosus* 

 Tro, olfactory peduncle ; UL, lobi inferiores ; VII, prosencephalon ; ZH, diencephalon ; 

 //, optic nerves; ///, oculomotor ; IV, j>athetic ; V, trigoniinal ; VI, abducent; VII, facial; 

 VIII, auditory ; IX, glossopharyngeal ; A", vagus. (From Wiedershcirn's Coinp. Anatomy.) 



the optic thalami. Attached to the roof is a slender tube 

 the epiphysis cerebri or pineal body (Gfp.), which runs forwards and 



