INDEX. 819 



Skin, continued. 



capillaries of, 171. 



cutis vera of, 425. 



epidermis of, 424. 



evaporation from, 440. 



excretion by, 434-39- 



exhalation of carbonic acid from, 



438. 

 of watery vapour from, 437. 



functions of, 425. 

 respiratory, 438. 



papillae of, 425-28. 



perspiration of, 435. 



rete mucosum of, 422. 



sebaceous glands of, 430. 



structure of, 421. 



sudoriparous glands of, 428. 

 Sleep, influence of on production of 

 carbonic acid, 224. 



in relation to heat of body, 243. 

 Smell, sense of, 631. 



conditions of, 631. 



different kinds of odours, 635. 



impaired by lesion of facial nerve, 

 552. 



impaired by lesion of fifth nerve, 

 548. 



internal excitants of, 636. 



limited to olfactory region, 634. 



relation to common sensibility, 



6 34- 



structure of organ of, 632. 

 subjective sensations of, 636. 

 varies in different animals, 635. 

 Sneezing, caused by sun's light, 488. 



mechanism of, 233. 

 Sniffing, mechanism of, 235. 



smell aided by, 632. 

 Soda, salts of in blood, 90. 



in solids and fluids, 27. 

 Sodium in human body, 27. 



chloride of, in albumen, 22. 

 Solid food, action of gastric fluid on, 



288. 



Solitary glands, 308. 

 Sonorous vibrations, how communi- 

 cated in ear, 684, e. s. 

 in air and water, 684. See Sound. 

 Soprano voice, 615. 

 Sound, 



conduction of by ear, 680. 

 by external ear, 681-84. 

 by internal ear, 690-93. 

 by middle ear, 684-90. 



Sound, continued. 



movements and sensations pro- 

 duced by, 698. 

 perception of, 693. 

 of direction of, 694. 

 of distance of, 695. 

 a state of the auditory nerve, 



696. 



permanence of sensation of, 695. 

 produced by contraction of muscle, 



59 1 .- 



production of, 693. 



subjective, 697. 



Sounds as expressions of passion, 

 615. 



classified, 615. 



of heart, 129. 



causes of, 130. 



Sources of nervous force, 485. 

 Spasms, reflex acts, 508. 

 Speaking, 615. 



mechanism of, 235. 

 Special sense. See Senses. 

 Spectrum-analysis of blood, 94. 

 Spectrum, ocular, 660-62. 

 Speech, 620. 



function of tongue in, 623. 



influence of medulla oblongata on, 



5*9. 

 Spermatozoids, development of, 735. 



form and structure of, ib. 



function of, 736. 



motion of, 735. 

 Spherical aberration, how corrected 



in the eye, 649. 

 Spheroidal epithelium, 39. 

 Sphincter ani, 



external, 351. 



internal, 316, 350. 



influence of spinal cord on, 504, 



509. 



Sphygmograph, 157. 

 Spinal accessory nerve, 563. See 



Accessory nerve. 

 Spinal cord, 490. 

 canal of, 493. 



a collection of nervous centres, 509. 

 columns of, 493. 

 commissure of, ib. 

 conduction of impressions by, 497- 



501. 



course of fibres in, 493. 

 decussation of sensitive impres- 

 sions in, 500. 



