INDEX 



"Visceral arches," architecture 

 of, 104; in predecessors of the 

 sharks, 104 

 Vision, the mechanism of, 189; 

 binocular, of Old World 

 monkeys, anthropoids and 

 man, 196; binocular, not 

 possible in Notharctus, 196; 

 developed by brachiating 

 habit, 198 

 Visual cortex of brain, 191 

 Visual purple (rhodopsin), 189 

 Vitreous humor, of the eye, 188 

 Vomer, 83 



Watson, D. M. S., studies of fossil 

 amphibia, 28; restoration of 

 skeleton of Eogyrinus from 

 data of, 28; contributions to 

 palaeontology, 86 



Weber, Max, evidence for con- 

 clusions on ancestry of 

 placental mammals, 51 



Williams, J. Leon, cited on three 

 types of central upper in- 

 cisors, 138, Fig. 73, 139 



Williston, S. W., contributions to 

 palaeontology, 86 



Williston's law, illustrated. Figs. 

 48-52, 78-82; loss of oper- 

 cular series, example of, 114 



Wolf, marsupial (Thylacinus), 

 under side of skull of. Fig. 

 53, 85; dentary of. Fig. 21, 37 



Worm, annelid, head of, 6; flat- 

 worm, 6, Fig. 2, facing 6 



Wyoming, Notharctus found in 

 Eocene formations of, 54 



Yerkes, R. M., cited on agreement 

 of mental traits in man and 

 anthropoid, 74; Fig. 39 copied 

 from photograph by, facing 64 



Zalambdalestes, skull and restora- 

 tion of head. Fig. 29, 50 



Ziska, Mrs. Helen, drawings made 

 by, 86 



Zygomatic arch, foreshadowed in 

 Mycterosaurus, 34; origin of 

 human, 89 



295 



