492 



INDEX 



Yellow Lupin. See Lupin, Yellow. 

 Yellow Mustard. See Mustard, Yellow. 

 Yield increased by breeding, 414,* 435-437. 

 Yucca. See Spanish Bayonet. 



Zea. See Corn. 

 Zinc, 161. 



affects flora, 351. 

 Zinnia, cross-pollination of, 304. 

 Zygospores, 396.* 



