604 INDEX 



Work, physiological, 4 



estimate of, in foot-pounds, 282, 562 



waste, a result of, 22 

 Wrist, 8 



Yellow elastic tissue, 558 



spot of eye, 42:5, 424 



wdth of cones in, 566 

 Young-Helmholtz theory of sensations of colour, 433, 436 

 Youth, bones afterwards united, are separated in, 14 



Zona pelUioida of ovum. 538 



Zootrope (^wof, an auiinal ; rponos, a turning), 448 



Printed in the United States of America. 



