LIST OF ILLUSTRATIONS xxix 



FIQ. PAGE 



186. Distance of the anterior and posterior canals (prolonged) from each other . 475 



187. Pigeon with membranous labyrinths removed 476 



188. Pigeon five days after removal of the right membranous labyrinth . . . 476 

 189. Pigeon twenty days after removal of the right membranous labyrinth . . 477 



190. The taste zone of the upper surface of the human tongue 483 



191. Course of the gustatory nerve fibers (from Leube's "Special Medical Diagnosis") 484 



192. Olfactometer of Zwaardemaker . 487 



193. Seebeck's siren . . 490 



194. Schema representing the relations of overtones to their fundamental . . . 492 



195. Resonator of Helmholtz .493 



196. Transverse section through the left auditory canal and tympanic membrane . 494 



197. Horizontal section through the tympanic cavity 495 



198. Hammer and anvil 496 



199. The organ of Corti of the human ear 500 



200. Action of the posterior crico-arytenoid muscle 503 



201. Action of the lateral crico-arytenoid muscle 503 



202. Laryngoscopic picture during quiet respiration 504 



203. Appearance of the vocal cords while producing a chest tone . . . . . 505 

 204. Position of the vocal organs in producing the sound of broad A .... 505 

 205. Position of the vocal organs in producing the sound of long E . . . 506 



206. Illustrating the refractive index 509 



207. Illustrating the refracting surfaces of the eye . . 510 



208. Illustrating a simple refracting system . . .511 



209. Illustrating the nodal points in a complex system . 511 



210. Position of the cardinal points in the schematic eye 513 



211. Section through the retina of a full-grown dog . ... . 515 



212. Illustrating the blind spot in the eye . -. . 516 



213. View of the rods and cones from the outer surface of the retina , \ . , . 517 



214. Diagram showing the visual angle ..... 518 



215. The static refraction of a hypermetropic, an emmetropic, and a myopic eye . 519 

 216. Method of demonstrating entoptic phenomena . . , '. . . 521 



217. Entoptic particle in the vitreous body . . . . /, . . . 522 



218. Illustrating spherical aberration 523 



219. Refraction of light rays in regular astigmatism (from Fuchs' "Text-book of 



Ophthalmology") 524 



220. Astigmatism chart 525 



221. Diagram illustrating chromatic aberration 526 



222. The iris of a cat at rest and on stimulation 528 



223. The iris of a cat with a sector isolated 528 



224. Method of demonstrating accommodation in the eye 530 



225. Reflection of images from the eye in accommodation 531 



226. The protrusion of the iris in accommodation 531 



227. Meridional section through the ciliary body 532 



228. Zonule of Zinn of an adult man 533 



229. Schema of the mechanism of accommodation according to Schon . . . 534 

 230. Schematic representation of the optic tracts (modified from Fuchs' "Text-book 



of Ophthalmology," drawn for this edition) 535 



231. Optogram formed in the visual purple 537 



232. Morphological changes produced in a frog's eye by light 538 



233. Disk with white and black sectors 539 



234 Illustrating the excitation of the retina successively by white and black sectors 539 

 235. Excitation of the retina as a function of the time exposed 540 



