Bui. 1489, U. S. Dept of Agriculture 
Plate I 
MlCROPHOTOGRAPHS OF A SECTION THROUGH A ROOT TlP OF CORN 
A, General structure (X 90) 
B, Group of individual cells, some of which ara in various stages of division (X 950) 
The writer is indebted to M. N. Pope for preparing the sections and to E. G. Arzberger for mak- 
ing the microphotographs 
