xiv LIST OF ILLUSTRATIONS 



FIG. PAGE 



96. Hippuris vulgaris, L. A case of air leaves followed by water leaves. 



[A. A.] 148 



97. Sium latifolium, L. Heterophylly. [A. A.] 149 



98. Sium latifolium, L. Submerged leaf. [A. A.] . . . .150 



99. Polygonum amphibium^'L. Water and land forms. [Massart, J. (1910)] 152 

 100. Polygonum amphibium, L. Epidermis of water and land leaves. 



[Massart, J. (1910)] 152 



loi. Alisma Plantago,\.. Seedlings. [A. A.] 153 



102. Alisma Plantago, L. Water form. [A. A.] 153 



103. Potamogeton natans, L. Effect of transferring land plant to water. 



[Goebel, K. (1891-1893)] 154 



104. Potamogeton Jiuitans, Roth. Effect of poor nutrition in water upon 



a land plant. [Esenbeck, E. (1914)] 158 



105. Potamogeton natans, L. Effect of growth as a cutting. [Esenbeck, E. 



(i9H)] 159 



106. Elodea canadensis, Michx. Leaf anatomy. [Schenck, H. (1886)] . 165 



107. Submerged stomates of Calla palustris, L. and Potamogeton natans, L. 



[Porsch, O. (1905)] 167 



108. Potamogeton densus, L. Leaf apex. [Sauvageau, C. (1891'^)] . . 167 



109. Myriophyllum spicatum, L. Leaf anatomy. [Schenck, H. (1886)] . 168 



1 10. Myriophyllum verticillatum, L. Trichomes. [Perrot, E. (1900)] . 170 



111. Callitriche verna, L. Leaf anatomy of land and water forms. 



[Schenck, H. (1886)] 170 



112. Hippuris vulgaris,!^. Rhizome. [Irmisch, T. (1854)] . . . 173 



113. Ranunculus trichophyllus, Chuix. Stem anatomy. [A. A.] . . 176 



114. Callitriche stagnalis, Scop. Stem stele of land and water forms. 



[Schenck, H. (1886)] 176 



115. Hippuris vulgaris, L. Relation of cauUne and leaf trace xylem. 



[A. A.] 178 



116. Myriophyllum spicatum, h. Stem anatomy. [Vochting, H. (1872)] 179 



117. Myriophyllum spicatum, h. Details of stem anatomy. [Vochting, H. 



(1872)] 179 



118. Potamogeton natans, L. Diaphragm of stem. [Blanc, M. le (1912)] . 184 



119. Hippuris vulgaris, L. Development of stem diaphragms. [A. A.] . 184 



120. Hippuris vulgaris, L. Origin of cortical lacunae in stem. [Barratt, K. 



(1916)] 185 



121. Stratiotes aloides, L. Origin of cortical lacunae in root. [Arber, A. 



(I9H)] . . ' .186 



122. jfussiaea peruviana, h. Aerenchyma. [Schenck, H. (1889)] . . 190 



123. Neptunia oleracea, Lour. Floating shoot. [Rosanoff, S. (1871)] , 191 



124. Nesaea verticillata, H. B. & K. Floating tissue. [Schrenk, J. (1889)] 193 



125. Potamogeton natans, L. Land form. [A, A.] .... 196 



