XIII 



PHYLUM CHORDATA 



147 



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

 the epiphysis cerebri or pineal body (Gp.\ which runs forwards and 



Tro Vff Gp f 



Zff Mf ' 



x 



FIG 775 Brain of Scyllium canicula. A, dorsal view ; B, ventral view; C, lateral view 

 3h -sis'- Z * rh 5 mboid T ahs (f urth ventricle); Gp, epiphysis; HH, cerebellum ; HS. A, hypo- 



Tro, olfactory peduncle ; UL, Idbi inferiors ; ' VH, prosencephafon ; ' Z^dLTfc^phaloii , : 

 ft^ P tlc ,. nerves ;//{, oculomotor ; IF, pathetic ; V, trigeminal ; VI, abducent ; VII, facial ; 

 VIII, auditory ; IX, glossopharyngeal ; A', vagus. (From Wiedersheim.) 



terminates in a slightly dilated extremity fixed to the membranous 

 part of the roof of the skull. Projecting downwards from its 



L 2 



