MEDULLA OBLONGA.TA. 



379 



the cerebellum, will be seen in the interior of each. This is the 

 ganglion of the corpus olivare. 



Behind the corpus olivare is a narrow white band, which de- 

 scends along the side of the medulla oblongata at the bottom of the 

 lateral sulcus. This is the situation of the respiratory tract of Sir 

 Charles Bell. 



The Corpora restiformia (restis, a rope) are the remaining 

 columns, of the medulla oblongata; they form its posterior segment, 

 and diverge superiorly to enter the cerebellum. Between the two 

 corpora restiformia posteriorly are two other white bands, which 

 diverge at the point of the calamus scriptorius, and join the cor- 



* The under surface or base of the brain. 1. The anterior lobe of one hemisphere 

 of the cerebrum. 2. The middle lobe. 3. The posterior lobe almost concealed by (4) 

 the lateral lobe of the cerebellum. 5. The inferior vermiform process of the cerebellum. 

 6. The pneumogastric lobule. 7. The longitudinal fissure. 8. The olfactory nerves, 

 with their bulbous expansions. 9. The substantia perforata at the inner termination 

 of the fissure of Sylvius ; the three roots of the olfactory nerve are seen upon the sub- 

 stantia perfora,ta. The commencement of the transverse fissure on each side is con- 

 cealed by the inner border of the middle lobe. 10. The commissure of the optic nerves. 

 11. The tuber cinereum, from which the infundibulum is seen projecting. 12. The 

 corpora albicantia. 13. The locus perforatus bounded on each side by the crura cere- 

 bri, and by the third nerve. 14. The pons Varolii. 15. The crus ccrebelli of one side. 

 16. The fifth nerve emerging from the anterior border of the crus cerebelli ; the small 

 nerve by its side is the fourth. 17. The sixth pair of nerves. 18. The seventh pair 

 of nerves consisting of the auditory and facial. 19. The corpora pyramidalia of the 

 medulla oblongata ; the corpus olivare and part of the corpus restiforme are seen at 

 each side. Just below the number is the decussation of the fibres of the corpora pyra- 

 mydalia. 20. The eighth pair of nerves. 21. The ninth or hypoglossal nerve. 22. 

 The anterior root of the first cervical spinal nerve. 



