CONTENTS 



21 



The Brain 



The Hind-brain or Rhombencephalon . 738 



The Mid-brain or Mesencephalon . . 741 



The Fore- brain or Prosencephalon . . 74] 



The Diencephalon 742 



The Telencephalon 743 



The Commissures 746 



Fissures and Sulci 747 



The Cranial Nerves '. 748 



THE SPINAL, CORD OR MEDULLA SPINALIS. 



Enlargements 751 



Fissures and Sulci 752 



The Anterior Median Fissure . . . 752 



The Posterior Median Sulcus . . 752 

 The Internal Structure of the Medulla 



Spinalis 753 



The Gray Substance 753 



Structure of the Gray Substance . 755 



The White Substance 758 



Nerve Fasciculi 759 



Roots of the Spinal Nerves 764 



The Anterior Nerve Root .... 764 



The Posterior Root 764 



THE BRAIN OR ENCEPHALON. 



General Considerations and Divisions . . 766 



The Hind-brain or Rhombencephalon. 



The Medulla Oblongata 767 



The Anterior Median Fissure . . . 767 



The Posterior Median Fissure . . . 767 

 Internal Structure of the Medulla 



Oblongata 775 



The Cerebrospinal Fasciculi . . 775 

 Gray Substance of the Medulla 



Oblongata 779 



Inferior Peduncle 782 



Formatio Reticularis .... 784 



The Pons 785 



Structure 785 



The Cerebellum 788 



Lobes of the Cerebellum . . . 788 



Internal Structure of the Cerebellum . 791 



The White Substance .... 791 

 Projection Fibres . . . .791 



The Gray Substance .... 794 

 Microscopic Appearance of the 



Cortex 794 



The Fourth Ventricle 797 



Angles 797 



Lateral Boundaries 797 



Choroid Plexuses 798 



Openings in the Roof 798 



Rhomboid Fossa 798 



The Mid-brain or Mesencephalon. 



The Cerebral Peduncles . . ... 800 



Structure of the Cerebral Peduncles . 801 



The Gray Substance .... 802 



The White Substance .... 803 



The Corpora Quadrigemina . . . 805 



Structure of the Corpora Quadrigemina 806 



The Cerebral Aqueduct 806 



The Fore-brain or Prosencephalon. 



The Diencephalon 807 



The Thalamencephalon 808 



Structure 810 



Connections 810 



The Metathalamus 811 



The Epithalamus 812 



The Hypothalamus 812 



The Optic Chiasma 814 



The Optic Tracts 814 



The Third Ventricle 815 



The Interpeduncular Fossa . . . .816 



The Telencephalon 817 



The Cerebral Hemispheres 817 



The Longitudinal Cerebral Fissure . . 818 

 The Surfaces of the Cerebral Hemi- 

 spheres 818 



The Lateral Cerebral Fissure . . . 819 



The Central Sulcus 819 



The Parietooccipital Fissure .... 820 



The Calcarine Fissure 820 



The Cingulate Sulcus 820 



The Collateral Fissure . . . . . 820 



The Sulcus Circularis 821 



The Lobes of the Hemispheres . . . 821 



The Frontal Lobe 821 



The Parietal Lobe 822 



The Occipital Lobe 823 



The Temporal Lobe 823 



The Insula 825 



The Limbic Lobe 825 



The Rhinencephalon 826 



The Olfactory Lobe ..... 826 

 The Interior of the Cerebral Hemi- 

 spheres 827 



The Corpus Callosum .... 828 



The Lateral Ventricles .... 829 



The Fornix 838 



The Interventricular Foramen . . 840 



The Anterior Commissure . . . 840 



The Septum Pellucidum .... 840 

 The Choroid Plexus of the Lateral 



Ventricle 840 



Structure of the Cerebral Hemi- 

 spheres . . 842 



Structure of the Cerebral Cortex . . 845 



Special Types of Cerebral Cortex . . 847 



Weight of Encephalon 848 



Cerebral Localization 849 



Composition and Central Connections of the Spinal 

 Nerves. 



The Intrinsic Spinal Reflex Paths ... 850 

 Sensory Pathways from the Spinal Cord 



to the Brain 851 



Composition and Central Connections of the Cranial 

 Nerves. 



The Hypoglossal Nerve 855 



The Accessory Nerve 855 



The Vagus Nerve 855 



The Glossopharyngeal Nerve 856 



The Acoustic Nerve 857 



The Vestibular Nerve . 860 



The Facial Nerve . . 861 



The Abducens Nerve . 861 



The Trigeminal Nerve 862 



The Trochlear Nerve . 863 



The Oculomotor Nerve 863 



The Optic Nerve . . 864 



The Olfactory Nerves . 866 



Pathways from the Brain to the Spinal Cord. 



The Motor Tract 870 



The Meninges of the Brain and Medulla Spinalis. 



The Dura Mater 872 



The Cranial Dura Mater .... 872 



Processes 873 



Structure 875 



The Spinal Dura Mater 875 



Structure 876 



The Arachnoid . 876 



The Cranial Part 876 



The Spinal Part 876 



Structure 876 



The Subarachnoid Cavity .... 876 



The Subarachnoid Cistern .... 876 



The Arachnoid Villi 878 



Structure 878 



The Pia Mater 878 



The Cranial Pia Mater 879 



The Spinal Pia Mater 879 



The Ligamentum Denticulatum . . 880 



