1050 



Respiration tension of gases in venous 

 blood, 679 

 tidal air, 646 

 value of nitrogen in, 672 

 ventilation, principles of, 661 

 vital capacity, 646 

 volumes of air respired, 645 

 voluntary control of, 690 

 Respiratory bronchioles, 637 

 center, 682, 691 



automatic activity of, 683 

 normal stimulus of, 692 

 reaction of, to change in carbon 

 dioxid pressure, 694 

 to oxygen pressure, 694 

 reflex stimulation of, 695 

 movements, electrical changes in, 



689 

 quotient, 705 



waves of blood-pressure, 656 

 Restiform body, 232 

 Retina, action current of, 333 

 acuity of vision in, 339 

 after-images from, 349 

 color-bUndness of, 351 

 contrasts in, 350 

 vision in, 345 

 corresponding points of, 369 

 distribution of color sense in, 354 

 entoptic phenomena, 363 

 function of rods and cones of, 356 

 fundamental and complementary 



colors, 347, 348 

 Ught adapted and dark adapted, 343 

 portion of, stimulated by hght, 332 

 projection of, on occipital lobes, 208 

 quahties of visual sensations from, 



345 

 size of fovea in, 339 

 theories of color vision in, 357 

 threshold stimulus of, 342 

 visual purple of, 334 

 Retinoscope, 329 



Reversible chemical reactions, 739 

 Rheoscopic frog preparation, 106 

 Rhodopsin, 334 



Ribs, action of, in inspiration, 640 

 Rice, relation to beriberi, 903 

 Rigor of muscle, 52, 68 

 Ringer's solution, 564 

 Ritter's tetanus, 92 

 Rivinus, ducts of, 747 

 Rods and cones of eye, functions of, 



356 

 Romberg's symptom, 236 

 Rubner's laws of growth, 1015 

 Rubrospinal tract, 179, 198 



Sacculus, functions of, 410 

 Sacral autonomics, 728, 729 

 Saliva, chorda, 751 



Saliva, composition of, 750 

 digestive action of, 750 

 general functions of, 762 

 secretory nerves for, 750 

 sympathetic, 751 

 Salivary glands, action of drugs upon, 

 757 

 anatomical relations, 747 

 histological changes during ac- 

 tivity, 754 

 structure of, 747 

 normal stimulation of, 758 

 secretory centers for, 759 



nerve-fibers of, 751 

 theory of secretory nerves, 753 

 Salts, absorption of, in stomach, 781 

 excretion of, 853, 924 

 general nutritive importance of, 924 

 Sarcolactic acid, 63 

 Sarcomere, 20 

 Sarcostyles, 19 

 Scurvy, 904 



Sebaceous glands, secretion of, 861 

 Secondary axes of a lens, 304 



degeneration, nerve-fibers, 123, 162 

 proteoses, 776 

 Secretagogues of gastric glands, 771 

 Secretin, gastric, 772 



pancreatic, 786 

 Secretion, 747 

 internal ,863 

 paralytic (saUva), 758 

 of bile, 814 

 of gastric juice, 770 

 of intestinal juice, 794 

 of pancreatic juice, 784 

 of saUva, 750 

 of sebaceous glands, 861 

 of sweat, 858 

 of urine, 830 

 Secretory nerves of sahvary glands, 



750 

 Semicircular canals, direct stimula- 

 tion of, 495 

 Fluorens' experiments upon, 403 

 structure of, 402 

 temporary and permanent effects 



of operations on, 404 

 theories of functions of, 407 

 Seminal vesicles, function of, 895 

 Senescence, 1010 

 Senses, classification of, 267 



cutaneous and internal, 274 

 SensibiHty, muscular, 284 

 of glans penis, 275 

 protopathic and epicritic, 274 

 Sensory aphasia, 218 

 areas of cortex, 201 

 paths in spinal cord, 167, 170 

 Sequence of heart-beat, 536 

 Serin, 789, 1019 

 Serodiagnosis, 743 



