Partial pressures of gases, 129 

 Parturition, 172 



spinal centre, 93 

 Passage of food from stomach to 



intestines, 167 

 Pathetic nerve, 206 

 Pathological paralyses, recovery 



from, 214 

 Paths of auditory impulses, 217 



of visual impulses, 216 

 Pepsin, 60 

 Peptones, 60 



absorption of, 73 

 Period of injection, 101 



of reception, 100 

 Peristaltic movements of esophagus, 



166 



of intestines, 168 

 Personal equation, 204 

 Perspiration, insensible, 39 

 Pettenkofer's test, 53 

 Pfliiger's law, 181 

 Phagocytes, 82 

 Phagocytosis, 82 

 Phenol, elimination of, 147 

 Physiological division of labor, 20 

 Pituitary body, 45 

 Placental circulation, 252 

 Plant cells, assimilation in, 22 

 Plasma of blood, 83 

 Plethysmograph, 25 

 Pneumogastric nerves, 208 

 Pneumograph, 226 

 Poikilothermous animals, 168 

 Polar bodies, 248 

 Polarization current, 190 

 Polymerization, 20 

 Polypeptids, 55 

 Polypnea, definition of, 130 

 Positive after-image, 235 

 Postganglion fibers of the sym- 

 pathetic, 116 

 Precipitins, 91 



Preganglionic fibers of the sym- 

 pathetic, 116 

 Presbyopia, 231 

 Pressor fibers, 118 



respiratory nerves, 134 

 Pressure, aortic, 100 



auricular, 101 



endocardiac, 100 



intracranial, 224 



intrapulmonary, 124 



intrathoracic, 124 



intraventricular, 100 



sense, 142 

 Primary colors, 235 



Primary optic centres, 216 



vision centres, 234 

 Proprioceptive fields, 205 

 Proteins of blood, 83 



combustion equivalent of, 140 



digestion of, 66 



molecular structure of, 54 



nutritive value of, 54, 140 

 Proteoses, 60 

 Protoplasm, 19 

 Pseudoglobulin, 83 

 Psychical secretion, 30 

 Ptyalin, action of, 58 

 Pulmonary circulation, 114 

 Pulse, arterial, 112 



characters of, 113 



volume of heart, 99 

 Pupil during accommodation, 229 

 Pupillary reflex to light, 232 



REACTION of degeneration, 182 

 of intestinal contents, 69 

 time, 206 

 Receptors, 90 



Reciprocal innervation, 198 

 Reduced reaction time, 204 

 Reflex action, simple, 196 



time value of, 204 

 Reflexes, inhibition of, 198 

 medical significance of, 205 

 reenforcement of, 203 

 superficial and deep, 205 

 voluntary control of, 188 

 Refractory period of heart, 106 



of nerve, 185 



Regeneration of nerve, 186 

 ! Rennin, action of, 60 

 Reproduction, 18 

 methods of, 248 

 i Reserve air, 127 

 I Residual air, 127 

 Respiration, 123 



associated movements of, 126, 135 

 at birth, 135 



nervous mechanism of, 133, 135 

 ratio to pulse, 127 

 sensory impulses on, 134 

 stimulation of nerves, 134 

 types, 126 

 Respiratory centre, 133 



in fetus, 254 

 movements, effect of, on blood 



pressure, 132 

 frequency of, 127 



