ILLUSTRATIONS 



FIGURE PAGE 



in the inner lining of the nerve tube or brain, with the 

 "rods" turned away from the light. 



A. Stage in which the dorsal pair of "eyes" (pineal 

 and parapineal) are beginning to grow outward, as 

 well as the "paired" eyes. 



B. Stage in which the eye stalks are forming. 



C. Stage in which the lens and retina are beginning. 

 D-I. Subsequent stages in the formation of the 



optic cup. 



98. — The Right Eyeball and Its Six Muscles . 190 



(From Plate, after Merkel and Kallins, Allgem. ZooL, 

 Gustav Fischer.) 



99. — The Right Eye of a Shark in Horizontal 



Section ....... 192 



(From Plate, after Franz, Allgem. ZooL, Gustav 

 Fischer.) 



100. — Diagram of Horizontal Section of the 



Right Human Eye ..... 193 



(Simplified from Plate, after Luciani, Allgem. ZooL, 

 Gustav Fischer.) 



101. — Tear-draining Canals of the Eye . . 194 



(After Keith.) 



102, — Front View of Infant and Young Skulls 



OF Anthropoids (A, B, C) and of Man (D) 197 



A. Chimpanzee. (After Selenka.) 



B. Gorilla. (After Selenka.) 



C. Orang. (After Selenka.) 



D. Human child. (Aiter M.a,Ttin, Lehrb d. AnthropoL, 

 Gustav Fischer.) 



103. — The Human Organ of Hearing and 



Balance ...... 203 



(A and C, after Cunningham.) 

 A. Transverse section. 



xxxvii 



