CONTENTS. xv 



II. SPECIAL SENSATIONS 391 



I. SENSE OF TOUCH AND FEELING 392 



Nervous papillae, 393. Tactile corpuscles, 394. Sensation 

 of varying temperatures, 396. Sensation of pressure, 

 397. Sense of localization, 398. 



II. SENSE OF TASTE 401 



Organs and seat of taste, savors, 402. Function of the chorda 

 tympani (Lussana and Schiff), 406. 



III. SENSE OF SMELL 408 



Odorous substances, 408. Nasal fossa, olfactory region, 410. 410 

 Olfactory nerves, 411. 



IV. SENSE OF HEARING 412 



External ear, 414. Middle ear, 416. Mastoid cells, 419. 

 Eustachian tube, 420. Internal ear, 421. Analysis of 

 sounds, 422. 



V. SENSE OF SIGHT 423 



1. Dioptrical apparatus or system, 424. Media of the eye, 



refraction, 426. Accommodation, 428. Emmetropia, 

 myopia, hypermetropia, etc., 431. Mechanism of accommo- 

 dation, 432. Astigmatism, 434. 



2. Membranes or envelopes of the eye, sclerotic and choroid 



coat, 435. Iris, 438. 



3. Sensitive membrane or retina, 440. Punctum ccecum, 444. 



Yellow spot, 445. Office of the rods and cones, 447. 

 Radiation, 448. Optical illusions, 449. Why we see ob- 

 jects erect and not upsidedown, 450. 



4. Appendages of the eye, muscles, 452. Lachrymal system, 



454. Meibomian glands, 456. 



TENTH PART. 



URO-GENITAL SYSTEM, EMBRYOLOGY. 



Origin of the uro-genital system, 458. Wolffian body, 459. 

 Uro-genital sinus, 459. 



I. URINARY SYSTEM 460 



A. Secretion of urine, 460. Henle's tubes, 461. Glomeruli of the 



kidneys, or Malpighian corpuscles, 461. Renal portal 

 vein, 462. Glomerular filtration, 462. Re-absorption of 

 albumen, 466. Excretion of urea, 468. 



B. Composition of urea, 468. Anhydrous urine, 469. Extractive 



matters, 470. Salts, 470. Kiesteine, 471. Influence of 

 the nervous system, 471. 



C. Excretion of urine, 472. Vesical epithelium, 472. How the 



bladder is completely emptied, 474. Micturition, 475. 



