INDEX. 



511 



Xanthophau, 282. 

 Xanthoproteic acid, 17, 20. 

 Xanthoproteic-acid reaction, 20. 

 Xylol, behavior in the body, 392. 



Yolk, of hen's egg, 291. 

 Yolk, membrane, 291. 



Zinc, IH the liver, 137; passage into the 



milk, 320. 

 ZoOerythrin, 325. 

 Zoofulvin, 325. 

 ZoSrubin, 325. 

 Zymogens, see various enzymes: Ren- 



net, Pepsin, and Pancreatic enzyme. 



llIRSITY 



