xvi LIST OF ILLUSTRATIONS 



FIG. PAGE 



154. Callitriche verna, L. Flowering shoot. [A. A.] .... 237 



155. Pontederia rotundifolia, L. Flowering shoot. [Hauman-Merck, L. 



(1913^)] 240 



156. Limnanthemum nymphoides, Hoffmgg. and Link. Fruit and seed. 



[A. A.] 240 



157. Limnanthemum nymphoides, Yio^vagg. zridlAv^. Fruit wall, [A. A.] 242 



158. Elatine hexandra, D. C. Germination of seed. [Klebs, G. (1884)] 245 



159. Zannichellia polycarpa,'i>io\tt. Fruit. [Raunkiaer, C. (1896)] . 246 



160. Trapa nutans, \j. Seed and germination. [Goebel, K. (1891-1895)] 247 



161. Xostera marina, L. Fruit. [Raunkiaer, C. (1896)] .... 248 



162. Transpiration experiment. [Sauvageau, C. (1891^)] . . . 262 



163. Callitriche autumnalis, L. Leaf apex. [Borodin, J. (1870)] . . 268 



164. Hydrocleis nymphoides, Buchen. Apical cavity of leaf. [Sauvageau, 



C. (1893)] 270 



165. Section across White Moss Loch. [Matthews, J. R. (1914)] . . 288 



166. Ruppia brachypus, J. Gay. Fruit. [Raunkiaer, C. (1896)] . . 319 



167. Potamogeton lucens, L. Range of leaf form. [Raunkiaer, C. (1896)] 339 



168. Potamogeton natans, L. Range of leaf form. [Raunkiaer, C. (1896)] 339 



169. " Lamina " of Pontederia cordata, L. and Eichhornia speciosa, Kunth. 



[Arber, A. (1918)] 341 



170. Leaf anatomy of Pontederiaceae. [Arber, A. (191 8)] . . . 342 



171. Leaf anatomy of 5^^zna. [Arber, A. (191 8)] '. . . . 345 



