INDEX 



327 



Pollen, 180 

 Polymorphism, 224 

 Polypeptides, 24 

 Polyzoa, 36 

 Potentials, 128 

 Producers, 96 

 Proliferation, 177 

 Proteins, 24 

 Protists, 30, 32 

 Protons, 57 

 Protophyta, 30 

 Protoplasm, 85 

 Protozoa, 30 

 Purpose, 126, 137 



Quality, 125 

 Quantity, 125 



Races, local, 242 



pure, 225, 229, 248, 257 

 Radiation, 57 

 Radioactivity, 274 

 Radiolaria, 31 

 Recapitulation, 290 

 Receptors, loi 



accessory, 104 



artificial, 104 



classes of, 102 



distance, 103 



intero, 103 



mechanism of, 119 



near, 102 



proprio, 103 

 Recessiveness, 229 

 Redifferentiation, 199 

 Reflex actions, 112 



automatism of, 146 



characters of, 147 



conditioned, 114 



integration of, 147 



purposes of, 148 



simple, 112 

 Regeneration, 169 

 Regression, 257 

 Rejuvenation, 174 

 Relation, 126 

 Repair, 169 

 Reproduction, 56, 130, 132, 165 



Reproduction, asexual, 178 



in fish, 177 



multicellular, 176 



plant, 174 



sexual, 179 



unicellular, 174 



vegetative, 179 

 Respiration, 45, 84 

 Response, 140 

 Revolutions, geological, 297 



Sea, original, 303 

 Sedentary animals, 41 

 Sedimentary rocks, 295 

 Sedimentation, 297 

 Segmentation, 191 

 Segregation, principle of, 229 

 Self-preservation, 131, 133 

 Senescence, 174 

 Sensations, 115 



classifiable, 117 



muscular, 118 



and perception, 114 



unities of, 120 



visceral, 118 

 Sense-organs, 47, 102 

 Sensori-motor system, loi 

 Sessile animals, 41 

 Sex, 176 



determination of, 183 



in plants, 184 

 Shelled animals, 42 

 Shell tissue, 48 

 Skeleton, 85 

 Solar energy, 62 

 Soma, 240 



Space and time, 121, 128 

 Special creation, 280 

 Species, 29, 222 

 Spermatozoon, 179 

 Sponges, 34 

 Spores, 178 

 Sport, 158 

 Statistics, 127 

 Sterility, 226 

 Stimulation, 102 

 Stimuli, 105 



conditioned, 107 



