THE MOST IMPORTANT CEREALS 159 



the coleorhiza and later the secondary roots appear about the time that 

 the plumule grows upward (Fig. 68). Collins describes some pueblo corn 



which is planted very deep in the soil at least a foot, or eighteen inches. 

 Corn with such a habit can reach the water in the deeper soil levels and is 

 adapted to an arid climate. 



