central, 84, 86 



diffuse, 87 



earthworm, 85 



effect of interstitial secretions, 98 



effectors, 85 



in relation to intelligence, 104 



influenced by environment, 95 



intricate structure of, 84 



man and higher animals, 84 



organization, 84 



receptors, 85 



reflex mechanism, 47 



rudiment, 44 



summary of evolution in man, 102 



sympathetic, 85 



vertebrates, 93 

 Neural groove, 44 



tube, 44 



Neuromuscular mechanism, 85 

 Neuromuscular system, evolution of, 



92 

 Neurones, 46 



internuncial, 84 



motor or efferent, 84, 85 



see Nerve cells 



sensory or afferent, 84, 85 

 New Zealand, mixed races, 176 

 Nitrogen, 99 

 Nose, development, 57 

 Notochord, 44 

 Nourishment of embryo, prenatal, 57 



Obercassel, Germany, 32 

 Old age, see Senescence 

 Oldoway ravine, 11 

 Olfactory, archipallium, 93 



cortex, 93 



organ, development of, 57 



organ, retrogression in, 73 



pits, 57 

 Ontogeny, 52, 164 



course of, 159 

 Organicism, 102 

 Organism, structural unit of, 39 



INDEX 199 



Organization, 134 



and a society, analogy between, 129 

 in relation to nervous system, 99-101 

 nervous, of sea-anemones, 86 

 sponges, 90-91 



Organs of body, relative rate of 

 growth, 66 



Orthogenesis, 156 



Osborn, H. F., 4, 18, 34, 35, 36 



Ouse, Sussex, 19 



Ovum, fertilization, 41, 42 

 structure, 42 



Pacific Islands, racial amalgamation 



in, 176 



Paleolithic period, 2 

 Pallium, 46 

 Pan vetus, 21 

 Pancreas, development, 51 

 Parables, 129 



Parathyroid gland, development, 49 

 Parr, Thomas, 70 

 Particles, protoplasmic, 152 

 Pathways, hereditary, 106 

 Pearl, R., 174, 175, 178 

 Pech de 1'Aze, France, 24 

 Perception, sense, 116 

 Personality, and nervous system, 81-83 



influence of sex glands upon, 98 

 Phantasms, 145 

 Phylogeny, 52, 164 



course of, 159 



provisional, of man and anthropoids, 



36 



Pineville, Missouri, 11 

 Pithecanthropus erectus, 12-16 

 Pituitary body, development, 49 

 Placenta, development, 58 



filter against bacteria, 59 



intervillous spaces, 58 



osmosis in, 58 



passage of materials through, 58-60 



separation of fetal and maternal 

 blood, 58 



