148 



Basic Structure of Vertebrates 



Fig. 139. A diagram of the brain of a four-month fetus as seen in sagittal sec- 

 tion. The figure shows the location of the more important brain commissures. 

 (Redrawn from Corning, after Burckhardt. Courtesy, Neal and Rand: "Chordate 

 Anatomy," Philadelphia, The Blakiston Company.) 



Fig. 140. Median section of the brain of a calf, (a) Aqueduct; (ac) anterior 

 commissure; (cc) corpus callosum (/) fornix; (h) habenula; (hy) hypophysis; (t) 

 infundibulum; (im) intermediate mass ("soft commissure") ; (//) lamina terminalis; 

 (mb) mammillary body; (pb) olfactory lobe; {oc) optic chiasma; (ol) optic lobes: 

 (p) pineal body; (r) recessus suprapinealis; (s) septum pellucidum; (III, IV) 

 third and fourth ventricles. (After Butschli. Courtesy, Kingsley: "Comparative 

 Anatomy of Vertebrates," Philadelphia, The Blakiston Company.) 



