THE MAMMALIAN NERVOUS SYSTEM 



55 



The tegmen fossce rhomboidece includes at its anterior border a 

 thin but nervous plate, the posterior medullary velum, bordering 



Thalamus 



Fasciculus 

 gracilis 



Fasciculus 

 cuneatus 



Ala cinerea 

 Trigonum 

 hypogloaai 



Tubercu- 

 lum 

 cuneatuiD 



Tractus 

 spinalis 

 trigemini 



Tractus 

 spinocere- 

 bellaris 

 dorsalis 



Fig. 11. — The dorsal surface of the medulla oblongata and midbrain of 

 the sheep. X 2. 



the attachment to the cerebellum, and further spinalward the 

 convoluted choroid plexus of the fourth ventricle (cf . Section 50) . 

 Notice that the fourth ventricle extends a short distance dorsal- 



