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 



Fig. 663. — Base of Brain of Ox. 

 1, Olfactory bulb; ;S, S', olfactory' strige; 3, trigonum olfactorium; 4y fossa lateralis; 5, piriform lobe; 6, optic 

 chiasma; 7, optic tract; 8, tuber cinereum; 9, cerebral peduncle; 10, pons; 11, corpus trapezoideum; IS, pyramid; 

 IS, cerebellum; 14, chorioid plexus of fourth ventricle: C.I., 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 o£E. 



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 



