8o 



BOTANICAL GAZETTE 



[JULY 



26 



27 



Figs. 26, 27.— Fig. 26, L. verticillatum: transverse section, showing the development 

 of the crescent-shaped xylem mass from the parallel-banded arrangement; px, proto- 



£, phloem; X500. 



transverse section, showing the 



>xylem; 



Fig. 28.— L. verticillatum: transverse section of the mature stem, showing the 



type 



