CONTENTS OF THE SECOND VOLUME. 



CHAPTEE XVI. 



INNERVATION, CONTINUED. 



Of SMELL. Cavities of the nose, 1 

 Structure of the nasal mucous mem- 

 brane, 3 

 The olfactory region, 5 



Nerves of the nose, 7 

 Conditions of smell, 11 

 Subjective phenomena, 13 



CHAPTER XVII. 



INNERVATION, CONTINUED. 



Of VISION, 14 



Anatomy of the eyeball, 15 



Sclerotic coat, 16 



Cornea, 17 



Its five layers, 18 



Choroid, 21 



Choroidal epithelium, 23 



Ciliary process of the choroid, 24 



Iris, 24 



Ciliary ligament and muscle, 27 



Retina, 27 



Its layers, 28 



Yellow spot, 30 



Vitreous body, 31 



Crystalline lens, 33 



Aqueous humour, 36 



Optic and other nerves, 37 



Muscles of the eye, 40 



Eyelids, 41 



Lacryrnal apparatus, 43 



Phenomena of vision, 44 



Formation of an image on the retina, 



46 



Visual angle, 46 

 Distinct and perfect vision, 46 

 Adaptation to distance, 47 

 Short and long sight, 48 

 Spherical and chromatic aberration 



corrected, 49 

 Reflexion from the bottom of the eye, 



51 



Excitability of the retina, 51 

 Duration of impressions, ocular spectra, 



53 



Blind spot, 54 



Action of the retina in vision, 56 

 Correct vision with an inverted image ; 



visual idea of direction, 57 ; of shape 



and size, 58 ; of motion in objects, 59 

 Doubleness of the organ, 59 

 Single vision, 60 

 Mr. Wheatstone's researches, 61 



Of HEARING, 63 



The organ in man and animals, 63 



External ear, 66 



Middle ear, 68 



CHAPTER XVIII. 



INNERVATION, CONTINUED. 



Internal ear, 71 



Osseous labyrinth, 72 



Spiral lamina and its zones, 76 



Cochlearis muscle, 79 



