LIST OF ILLUSTRATIONS. XXI 



FIG. PAGE 



143. Myopic eye, in vision at long distances . . . . (Wundt) 545 



144. Single and double vision, at different distances .... 547 



145. Skull, as seen by the left eye 548 



14(3. Skull, as seen by the right eye 548 



147. Rood's apparatus, for measuring duration of electric spark . . 551 



148. Ossicles of the human ear (Rudinger) 555 



149. Ossicles of the ear, in situ (Rudinger) 556 



150. Bony labyrinth of the human ear 559 



151. Bony cochlea of the human ear .... (Crtiveilhier) 563 



152. Organ of Corti 505 



153. Cysticercus cellulose (Davaine) 575 



154. Trichina spiralis ; encysted 576 



155. Infusoria, of various kinds . . . (Ehrenberg and Stein) 577 



156. Stylonychia mytilus ; unimpregnated and impregnated . (Stein) 580 



157. Cells of Bacterium termo 581 



158. Human ovum 584 



159. Human ovum, ruptured by pressure 585 



160. Female generative organs of frog ....... 586 



161. Mature frog's eggs 587 



162. Female generative organs of fowl 588 



163. Diagram of the fowl's egg 589 



164. Uterus and ovaries of the sow 590 



165. Generative organs of the human female ...... 591 



166. Spermatozoa 593 



167. Graafian follicle, near the period of rupture 602 



168. Ovary with Graafian follicle ruptured 603 



169. Human Graafian follicle, ruptured during menstruation . . . 609 



170. Corpus luteum of menstruation, three weeks old .... 610 



171. Corpus luteum of menstruation, four weeks old .... 610 



172. Corpus luteum of menstruation, nine weeks old . . . .611 



173. Corpus luteum of pregnancy, two months old . . . . 613 



174. Corpus luteum of pregnancy, four months old .... 613 



175. Corpus luteum of pregnancy, at term 614 



176. Segmentation of the vitellus 617 



177. Impregnated egg, with embryonic spot 620 



17*. Frog's egg, in an early stage of development 621 



179. Frog's egg, in process of development r.21 



180. Frog's egg, farther advanced . . . . . . . '>_! 1 



181. Tadpole, fully developed 



182. Phases of segmentation, in the fowl's egg . . . (Coste) 025 



183. Transverse section of the blastoderm, showing its three layers 



(Kolliker) 628 



184. Transverse section of embryo chick, showing open medullary groove 



(Kolliker) 630 



185. Transverse section of embryo chick, showing narrowed portion of 



medullary groove (Kolliker) 631 



186. Transverse section of embryo chick, showing closed medullary canal 



(Kolliker) 631 



187. Embryo chick, at thirtieth hour of incubation . . (Kolliker) 632 



188. Embryo of chick, at thirty-sixth hour of incubation . (Kolliker) 634 



189. Embryo of chick, about fortieth hour of incubation . (Kolliker) 634 



190. Portion of the area vasculosa (Kolliker) 636 



