CONTENTS 



PLATES I -XV. 











PAGES 



IISITRODUCTION 



. 65 



MORPHOLOGY OF THE VEGETATIVE ORGANS 



. 69 



Stem 





. 69 



A. General Characters ........ 



69 



B. Brandling .......... 



. 69 



1. 



Branching in Ruppia maritima ..... 



. 69 





a. Vegetative Branch System ..... 



. 69 





b. Iniiorescent Branch System 



. 71 



2. 



Comparative Study of the Branching of the Potamoge- 







tonaceae ........ 



. 72 



C. Anatomical Structure 



74 



1. 



Grov^ing Point 



74 



2. 



Stem Structures in. the Vegetative Region 



75 





a. Upright Stem 



75 





(1) Epidermis 



75 





(2) Cortex 



75 





(a) Outer Cortex ....... 



76 





(b) Middle Cortex ...... 



77 





(c) Inner Cortex ....... 



77 





(3) Endodermis 



78 





(4) Vascular System 



78 





(a) Course of Vascular Bu?idles .... 



78 





(b) Structure of Vascular Bundles 



80 





b. Rootstock 



82 



3. 



Stem Structm-es in the Eloral Region 



83 





a. Peduncle . . . . . . , . 



83 





(1) General Characters ...... 



8a 





(2) Anatomical Structure . . . . . . ' 



83 





(3) Coiling of the Peduncle 



85 





b. Rhachis 



85 





c. Stipe 



85 



4. 



Brief Comparative Study of the Stem Anatomy of the 







Potamogetonaceae ...... 



86 



Leaf 



. 



86 



A. Enumeration of Kinds of Leaves ...... 



86 



B. Arrangement 



86 



C. Ordinary Eoliage Leaves 



87 



