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TEXT-BOOK OF PHYSIOLOGY 



column of the cord. As the fibers pass upward, however, they diverge in several 

 directions. The fibers of the crossed pyramidal tract cross the median line, 

 as previously stated, to enter into the formation of the anterior column; 

 the fibers of the direct cerebellar tract gradually curve backward, and in so 



FIG. 235. ANTERIOR OR VENTRAL 

 VIEW OF THE MEDULLA OBLONGATA 

 AND ISTHMUS, i. Infundibulum. 2. 

 Tuber cinereum. 3. Corpora albi- 

 cantia. 4. Cerebral peduncle. 5. 

 Tuber annulare. 6. Origin of the 

 middle peduncle of the cerebellum. 

 7. Anterior pyramids of the medulla 

 oblongata. 8. Decussation of the an- 

 terior pyramids. 9. Olivary bodies. 

 10. Restiform bodies, n. Arciform 

 fibers. 12. Upper extremity of the 

 spinal cord. 13. Ligamentum dentic- 

 ulatum. 14, 14. Dura mater of 

 the cord. 15. Optic tracts. 16. 

 Chiasm of the optic nerves. 17. 

 Motor oculi communis. 18. Patheti- 

 cus. 19. Fifth nerve. 20. Motor 

 oculi externus. 21. Facial nerve. 22. 

 Auditory nerve. 23. Nerve of Wris- 

 b e r g. 24. Glosso-pharyngeal nerve. 

 25. Pneumogastric. 26, 26. Spinal 

 accessory. 27. Sublingual nerve. 28, 

 29, 30. Cervical nerves. (Sappey.} 



FIG. 236. POSTERIOR OR DORSAL VIEW 

 OF THE MEDULLA OBLONGATA, ISTHMUS, 

 AND BASAL GANGLIA, i. Corpora quad- 

 rigemina. 2. Corpus quadrigeminum an- 

 terius (pregeminum). 3. Corpus quadri- 

 geminum posterius (post-geminum). 4. 

 Tract of fibers (brachium) passing to the 

 corpus geniculatum externum. 5. Tract of 

 fibers (brachium) passing to 6, the corpus 

 geniculatum internum. 7. Posterior com- 

 missure. 8. Pineal gland. 9. Superior cere- 

 bellar peduncle. 10, n, 12. The valve of 

 Vieussens. 13. The pathetic nerve. 14. 

 Lateral groove of the isthmus. 15. Triangu- 

 lar bundle of the isthmus. 16. Superior , 

 cerebellar peduncle. 17. Middle cerebellar 

 peduncle. 18. Inferior cerebellar peduncle. 

 19. Antero-inferior wall of the fourth ventri- 

 cle. 20. Acoustic nerve. 21. Spinal cord. 

 22. The postero-median column. 23. The 

 posterior pyramids. (Sappey.) 



doing unite with other fibers to form the restiform body, after which they 

 enter the cerebellum by way of the inferior peduncle. Situated between the 

 anterior pyramid and the restiform body is a small oval mass, the olivary 

 body, composed of both white and gray matter. 



