no 



The Waterulies. 



The internodes above the epicotyl are not developed, but the stem 

 gradually thickens and enlarges into a miniature tuber. In nearly all of the 

 genus the plant is now essentially mature ; it needs only to enlarge. But 

 in Eu-castalia a marked change takes place. The internodes after a time 



Fio. 60. Seedling leaves : (a), N. amazonum ; a, first leaf ; b, second (first broad) leaf ; c, third leaf ; 

 e, epicotyl ; p, primary root ; si, first secondary root ; (b). If. catrulea ; 1. 2, 8, 4, first and following broad 

 leaves ; (e). first floating leaf, X. odorata giyantea ; (d), If. lotus var., 1, 2, , 4, first and following leaves, the 

 last very young ; (e), N. zanzibariensis ; 1, 2, 8, first and following broad leaves ; If), If. tetroyoiia, 1, 2, 8, first 

 and following broad submerged leaves ; 1 fi, first floating leaf. Twice natural size. 



regularly, but slightly, elongate, and the stem suddenly becomes plagio- 

 tropic ; thus a tiny horizontal rhizome is produced. From this point 

 onward maturity is simply a matter of size. 



In structure the characteristic features of the order are evident at a 

 very tender age. While the primary root is still a mere papilla, the root- 

 cap consists of a single layer of cells, and behind it are three to four close 



