THE BRAIN 



163 



hypophysis and glandular saccus vasculosus are present, but these 

 vary much in the degree of their development. The saccus 



Lol, 



FIG. 133. BRAIN OF SALMON. (A, dorsal; B, ventral; and C, lateral view. ) 



VH, prosencephalon ; Pall, pallium (in part removed), and EG and Bas.G, basal 

 ganglia (corpora striata) of the prosencephalon ; 'L.ol, olfactory lobe; G.p, 

 pineal body ; Jnf, infundibulum ; Hyp, hypophysis ; Sr, saccus vasculosus ; 

 UL, lobi inferiores ; Tr.opt, optic tract ; Ch, chiasma ; MH, mid-brain ; 

 HH, cerebellum ; NH, medulla oblongata ; Med, spinal cord ; I-X, cranial 

 nerves ; 1 and 2, first and second spinal nerves (the first represents the 

 hypoglossal, XII). 



vasculosus opens by several apertures into the infundibulum, and 

 is surrounded by a blood-sinus. 



M 2 



