PAPERS ON BIOLOGY AND AGRICULTURE 99 



Fig. 13. Diagram of bundles in the epicotyl of the same seedling. 



Constructed by means of a model from the serial transverse 



sections 10 u thick. The base plate shows the arrangement 



of bundles thru the lower part of the epicotyl, from the 



region where the cotyledons are cut off. to the region where 



the adventitious root strands (AR) arise. 



S\ S 2 , S 5 , S 4 .— central epicotyl bundles. 



F 1 . F 2 , F 3 . — first, second, and third leaves. 



LG 1 . LG 2 . LG 3 , — first, second, and third leaf gaps. 



L\ L 12 , — peripheral vascular strands. 

 Fig. 14. Transverse section of a bundle from the rhizome of Nelumbo 



lutea. 

 Note: In the preparation of the model of the oldest seedling pictured, 

 comparisons were made with still older seedlings to determine 

 certain points difficult to ascertain in so young a seedling. Some 

 of the ideas thus gained are incorporated in the model. 



