INDEX. 



1049 



Sound-sensation, vibration-rate necessary to pro- 

 duce, 826 



Sound-waves, production of, 825 

 Sounds, audible, limits of, 826 

 heart-, 410 



practical application of observation of, 416 

 musical, analysis of, 829 

 respiratory, 517 



Space-perception, illusions of, 796-799 

 Specific heat of the body, 948 

 Species, effect of, on respiratory quotient, 545 

 influence of, on heat-dissipation, 592 

 on heat-production, 590 

 on the respiratory rate, 533 

 on the volume of gases respired, 537 

 Spectroscope, the, 338, 339 

 Spectrum, absorption of bile, 262 

 of blood, 338 



of carbon-monoxide haemoglobin, 342 

 of hsematin, 342 

 of methsemoglobin, 342 

 of oxyhsemoglobiii, 339, 340 

 of reduced haemoglobin, 340, 341 

 colors, number of, 778 

 defined, 338 



intensity of the, distribution of the, 786 

 Speech, 861-877 



impairment of, cause of, 698 

 Speech and hearing centres, relations of, 871 

 " Speech-centre," Broca's, 698 

 Spermatocyte, 884 

 Spermatozoa, the, 882 



action of the, in entering the ovum, 904 

 contractility of, 35 

 discovery of, 882, 936 

 duration of life of the, 903, 904 

 locomotion of the, 883, 903 

 maturation of, 884 

 passage of the, time required in, 903 

 presence of, in the testes of the aged, 885 

 production of, average, 883 

 structure of human, 882, 883 

 Spermatozoon and ovum, place of union, 903 

 Spermiue, 211, 884 

 Sphincter ani pylorici, 315 

 of the cardiac orifice, 312 

 pyloric, 315, 319 

 urethra, 328 

 vesicse internus, 328 

 Sphincters, rectal, function of, 324 

 " Sphygmogram," the, 434-436 

 Sphygmograph, the, 434 

 Sphygmomanometer, the, 433 

 Spinal cord, nerve-fibres in the, ending of, 85 

 reactions of portions of the, 704 

 weight of the, 723 



and of the brain, 715-724 

 Spirometer, the, 535 

 Spleen, composition of, chemical, 273 

 extirpation of, result of, 272 

 functions of the, 272, 273 

 movements of the, 272 

 nerves of the, vaso-motor, 499 

 theory of reproduction of blood-corpuscles, 



343 



41 Staircase contractions," 72, 110 

 Standing, muscular action in, 846, 859 

 Stapedius (muscle), 814 

 Stapes, the, 810, 812 

 Starch, 1007 



action of amylolopsin on, 243, 244 

 animal, 1008 



conversion of, 223, 224, 257 . 

 digestion of, intestinal, 247 

 Starvation, effect of, on body-metabolism, 301 



on the nervous system, 737 

 Stature, decrease of, in old age, 929 



Stature and weight of both sexes at birth, 925 

 Steapsin, 244 



action of, influence of temperature on, 245 



reaction of, 244 



value of, in digestion and absorption of fats, 



245 



Stenson's duct, 158 

 Stereoscope, the, 801 

 Sternum, respiratory movements of, 509 

 Stimulants, action of, upon the pancreatic secre- 

 tion, 177 



as articles of diet, 297 



Stimulation, electrical, of the cut vagus, results 

 of, 568, 569 



muscle, effect of artificial, compared with 

 normal, 126 



nerve, relation of the composition of the secre- 

 tion to the strength of, 164 



of secretory nerve-fibres, effect of, 163, 164 



retinal, 788, 791 



vagus, effect of, on the heart, 453-457 

 Stimuli, number of, necessary to elicit a response 

 in a nerve-cell, 625 



rapidly-repeated, effect of, on muscle and 

 nerve, 72, 73 



reaction to. See Reflex action. 

 Stokes' reagent, 341, n. 

 Stomach, absorption in, 252, 253 



bacteria of the, 248 



coats of the, 315 



contents, ejection of the, 318, 319, 325, 326 



digestion in the, peptic, 228-232 



functions of the, 237 



glands of the, secretory, 178-182 



movements of the, 315, 316 



muscles of the, 315, 319 



not essential in digestion, 237 



physiology of the, 237 



secretions of, acidity of, 226-228 



self-digestion of, exemption from, 236 

 Striae gravidarum, 915 

 Stromuhr, the, 391 

 Strontium, 970 

 Strychnin, influence of, on the diffusibility of 



nerve impulse, 652 

 Succus entericus, 184, 286 

 Suffocation. See Asphyxia. 

 Sugar of the body, 292, 293 

 Sugars, absorption of, 253, 257 

 Sulphate, calcium, 967 



sodium, 966 

 Sulphates of urine, conjugated, 279 



quantity of, 280 

 Sulphide, ferro-, 972 

 Sulphur, 949 



detection of, 950 



metabolism of, 951 

 Suprarenal capsules, 210 

 Sutures, union of bone by, 855 

 Swallowing, act of, nervous control of, 314 



mechanism of, 311-313, 866 



stages of, 310, 311 

 Sweat, 198-200, 281 



color and odor of, 281 



composition of, 198, 199, 281 



elimination of urea in, 275 



influence of, on heat-dissipation, 595 



reaction of, 199, 281 



specific gravity of, 199, 281 

 Sweat-centres, in central system, 200 

 Sweat-glands, action of nerve-fibres on, 199 

 distribution of the, 281 

 effect of drugs on the, 200 

 effect of temperature on the, 200 

 histology of, 198 

 number of human, 198 

 secretion of the, 198-200 



