836 THE NERVOUS SYSTEM OF THE OX 
by a plexus of vessels. It is much narrower and thicker than that of the horse. 
The infundibulum is relatively long and slopes downward and backward. 
The cerebral hemispheres are shorter, higher, and relatively wider than in the 
horse. The frontal poles are small, the occipital, large. The length from pole to 
pole is about the same as the greatest transverse diameter of the two hemispheres. 
Longitudinal fissure 
Fic. 663,—Base or BRAIN OF Ox. 
1, Olfactory bulb; 2, 2’, olfactory strie; 3, trigonum olfactorium; 4, fossa lateralis; 6, piriform lobe; 6, optic 
chiasma; 7, optic tract; 8, tuber cinereum; 9, cerebral peduncle; 10, pons; 17, corpus trapezoideum; 12, pyramid; 
13, cerebellum; 14, chorioid plexus of fourth ventricle; C.J., first cervical nerve roots. The stumps of the cranial nerves 
are designated by Roman numerals. The hypophysis has been removed and its contour is indicated by dotted line. 
The central black area is the infundibular recess of the third ventricle opened up when the infundibulum is torn off. 
Viewed from the side, the dorsal surface is strongly convex. The highest point of 
the dorso-medial border is a little in front of its middle and forms a marked promi- 
nence termed the sagittal or marginal pole (Polus sagittalis s. prominentia mar- 
ginalis dorsalis). Anterior to this the border drops abruptly, being cut into by the 
deep transverse fissure. The arachnoid on the basal and anterior parts of the 
hemispheres is usually pigmented. The corpus callosum extends through a little 
