14 CO XT E NTS. 



PAGE 



mixtures, 333 — Color-theories, 335 — Color-blindness, 338 — The intensity of light 

 sensations, 339 — The luminosity of different colors, 340 — The function of rods and 

 cones, 341 — The saturation of color-sensations, 342 — Retinal stimulation, 343 — The 

 latenl period <>f light-sensations, 343 -The rise to maximum of light-sensations, 3t3 

 — The fatigue of tin- retina, 344— The after-effect of stimulation, 315 — After-images, 

 346 — Color-contrasts, 346 -The perception of space. 347— Irradiation, 34!) — The false 

 judgments of snbdivided Bpace, 350 — The perception of distance, 354 — Binocular 

 vision, 356' — Pseudoscopic vision, 357— Binocular combination of colors, 358 — Corre- 

 sponding points, 358- Visual illusions, 360. 



B. The Eab and Hearing (By Hknkv Skwall) 362 



The anatomy and histology of the ear, 362 — The external ear, 362 — The middle ear, 



36:; Movements of the ear-ossicles, 367 — The Eustachian tube, 369— The muscles of 

 the middle ear, 369- The vibrations of the tympanic membrane, 370 — The structure 

 of the internal ear, 371— The general anatomy of the cochlea, 374 — The transmission 

 of vibrations through the labyrinth, 376 — The membranous cochlea and the organ of 

 Corti, 376 — The theory of auditory sensations, 380. 



C. The Relations Between Physical and Physiological Sound 381 



Production of sound-waves, 381 — Loudness and musical pitch, 381 — The tympanic 



membrane as an organ of pressure-sense, 382— Overtones and quality of sound, 3s3 — 

 Analysis of composite tones by the ear. 384 — Inharmonic overtones, 386 — The produc- 

 tion n( heats, 386 — Harmony and discord. 3S7 — Combinational tones, 387 — Auditory 

 fatigue, 387 -Imperfections of the ear. 388 — Perceptions of time-intervals, 388 — Musi- 

 cal tones and noises, 388 — Functions of different parts of the ear, 388 — The judgment 

 of direction and distance, 389. 



D. CUTANEOU8 AND MUSCULAB SENSATIONS 390 



General importance of the cutaneous and muscular sensations, 390 — Ending of 

 sensory nerve-fibres in the skin, 391 — Relations of stimulus to the touch-sensations, 

 392 — The localization of touch-sensations. 394 — Pressure-points, 396 — The importance 

 of the end-organ, 396— Touch-illusions. 396 — The temperature-sense, 397 — Cold and 

 warm points. 398 — Common sensation and pain, 399 — Transferred or sympathetic 

 pains; allochiria, 400 — Muscular sensation, 401 — Hunger and thirst, 404. 



E. The Equilibrium of the Body ; the Function of the Semicibculab Canals 404 

 The sense of equilibrium, 404 — Disturbances of the sense of equilibrium, 405 — 



Theory of the relation of the semicircular canals to equilibrium, 406 — The relation of 

 the vestibular sacs to equilibrium, 407. 



F. Smell 408 



Structure of the olfactorv epithelium, 408 — The production of olfactory sensations, 



409. 



G. Taste 410 



Structure of the taste-buds, 410 — The production of taste-sensations, 411 — Classifica- 

 tion of taste-sensations, 412 — Specific energy of taste-nerves, 413. 



PHYSIOLOGY OF SPECIAL MUSCULAR MECHANISMS 414 



A. The Action of Locomotor Mechanisms (By Warren P. Lombard) 414 



The articulations, 414— Sutures, 414— Symphyses, 414— Syndesmoses, 414— Diar- 



throses, 115— The lever-action of muscles on bones, 417— The act of standing, 418 — 

 The act of locomotion. 420— Walking, 420— Running, 421. 



B. Voice and Speech (By Henry Sewall) 421 



Voice-production, 121 — Functions of the epiglottis, 422— Ventricular hands and 



ventricles of Morgagni, 122— The true vocal cords, 423— The cartilages of the larynx. 

 425— The muscles of the larynx. 125— Specific actions of the laryngeal muscles, 427— 

 The nerve-supply of the larynx, 428 — The laryngoscopy appearance of the larynx, 

 429— The production of voice,' 130— Loudness and pitch of voice. 430— Quality of voice, 

 130 Arrangements for changing the pitch of the voice, 432— The vocal registers, 132 

 A whistling register, 433— Speech, 433— The classification of vowel sounds, 434— 

 Whispering, 436 The production and classification of consonants, 436. 



REPRODUCTION (By Frederic S. Lee) 439 



A. Bepboductiom in Genebal 439 



Asexual reproduction, 439 — Sexual reproduction, 440— Origin of sex and theory of 



reproduction, 111 — Primary and secondary sexual characters, 442 — The sexual organs, 

 443. 



B. The Male Repboductive Organs : • 413 



Structure and properties of the spermatozoon, I 13- Maturation of the spermatozoon, 

 445— The composition of semen, 445 -The testis, 146 Tin' urethra. 1 18— The prostate 

 gland, II- -Cowper's glands, 448 — The penis, 41-". 



