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ANATOMY OF 



A transverse section of the brain, on a level with the lateral ventricles. The 

 upper part of the corpus callosum, together with the fornix, removed, so as to 

 expose the upper part of the lateral ventricles, the middle ventricle, the corpora 

 striata, the optic thalami, tubercula quadrigemina, and the pineal gland with its 

 prolongations. The valve of Vieussens and the cerebellum are divided in the 

 middle line, and separated to expose the fourth ventricle and the calamus scrip- 

 torius. 1 . Transverse section of the frontal bone. 2, 2. Cranial surface of its 

 orbitar plate. 3. Anterior extremity of the cerebral hemispheres. 4. Posterior 

 extremity of the same hemispheres. 5. White substance of the hemispheres. 

 6, 6, 6. Thin grey substance. 7. Anterior part of the interlobular fissure. 

 8. Cut in the anterior extremity of the corpus callosum. 9. Bent back portion 

 of the anterior extremity of the corpus callosum, placed between the corpora 

 striata. 10. Anterior extremity of the corpus striatum. 11. Posterior ex- 

 tremity of the corpus striatum, and upper part of the lateral ventricle. 12. Tha- 

 lamus opticus. 13. Semicircular band between the thalamus and corpus 

 striatum. 14, 14. Anterior pillars of the fornix, divided near their origin. 

 15. Anterior, and, 16. Posterior, extremity of the middle ventricle. 17. Nerv- 

 ous band or middle commissure, uniting the thalami in the interior of the 

 middle ventricle. 18. Posterior commissure. 19. Pineal gland. 20. Medul- 

 lary prolongations of the pineal gland in the internal part of the optic thalami. 

 21. Tubercula quadrigemina superiora. 22. Tub. quad, inferiora. 23. Crucial fur- 

 row between them all. 24, 24. Valve of Vieussens divided, and each half turned 

 back. 25. Vertical section of the cerebellum and arbor vitae. 26, 26. Supe- 

 rior surface of the cerebellum. 27. Fourth ventricle. 28. Central groove 



