CONTENTS 



CHAPTER I PAGE 



ORIGIN AND FUNCTION OF THE NERVOUS SYSTEM 17 



The Diffuse Nervous System of Ccelenterates 19 



The Central Nervous System 20 



CHAPTER II 



THE NEURAL TUBE AND ITS DERIVATIVES 24 



The Brain of the Dogfish 26 



Development of the Neural Tube in the Human Embryo 31 



CHAPTER III 



HlSTOGENESIS OF THE NERVOUS SYSTEM 37 



Development of the Neuron 37 



Development of the Spinal Nerves 40 



Differentiation of the Spinal Cord 42 



CHAPTER IV 



NEURONS AND NEURON-CHAINS 43 



Form and Structure of Neurons 43 



Interrelation of Neurons 49 



The Neuron as a Trophic Unit 51 



The Neuron Concept 52 



Neuron Chains 53 



CHAPTER V 



THE SPINAL NERVES 56 



Metamerism 58 



Functional Classification of Nerve-fibers : 60 



The Spinal Ganglia 62 



Somatic Sensory Fibers and Nerve Endings 66 



CHAPTER VI 



THE SPINAL CORD 73 



External Form and Topography 73 



The Spinal Cord in Section 78 



Microscopic Anatomy 85 



The Spinal Reflex Mechanism 91 



CHAPTER VII 



FIBER TRACTS OF THE SPINAL CORD 95 



Intramedullary Course of the Dorsal Root Fibers 95 



Afferent Paths in the Spinal Cord 98 



Ascending and Descending Degeneration in the Spinal Cord 105 



Long Descending Tracts of the Spinal Cord 108 



CHAPTER VIII 



GENERAL TOPOGRAPHY OF THE BRAIN 113 



Anatomy of the Medulla Oblongata 118 



Anatomy of the Pons 123 



The Fourth Ventricle 125 



The Mesencephalon 129 



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