700 ANIMAL PHYSIOLOGY. 
Xanthin, 194. . Zona radiata, 55. 
Zodgloea, 18. 
Yawning, 407. Zygospore, 17. 
Yeast, morphology, chemistry, and physi- | Zymogen, 328. 
ology of, 9, 10. 
THE END. 
