74 THE WATERLILIES. 



the access of water to the embryonic tissues. The first idea could apply 

 to the hairs on mature leaves as well as to the younger. It would be use- 

 less to assert that either purpose is unimportant. 



In a few cases the leaves of Nymphaea have been viviparous. Plan- 

 chon (1852, <r) records this for "N.stdlata" (probably N. micrantha) as 

 grown by Van Houtte. The plant came from English cultivators, with 

 whom it had never shown this tendency. The new plant springs from the 

 upper surface of the leaf just over the insertion of the petiole. "Already 

 visible," says Planchon, "though very small on the young leaf, the axis but 

 a tubercle with very rudimentary leaves, [the bud] remains almost station- 

 ary on the adult and functional leaf so long as this retains its connection 

 with the living plant. If the leaf is detached artificially or by decay of the 

 petiole, it puts out roots, develops its leaves rapidly, and seems to hasten 

 to live an independent life." 1 Further details of the process have not been 

 recorded. It was observed in N. micrantha Guill. & Perr. and given thus 

 in the description of the species : " Folia . . . inter lobos saepius bulbifera, 

 bulbillis sphaericis pubescentibus." Hooker ( 1850) also records the fact 

 in a few words in describing N. micrantha in the Botanical Magazine, 

 where the leaf figured is viviparous, and Paxton (1853, a) mentions it in his 

 " Flower Garden." Lehmann (1853, a) went so far as to establish a " Tribe 

 III Bulbophyllon" for his JV. vivipara, N. guineensis Thonn., and A^. mi- 

 crantha Guill. & Perr. We have not considered these as specifically distinct. 



Water-leaves are produced in all seedling Nymphaeas to the number 

 of 2 (N. flava) to 15 or 16 before any floating leaves. Of these more 

 will be said in another chapter. In species which have dry resting tubers 

 the first leaves produced on resuming growth are also entirely submerged. 

 N. flavo-virens alone, with its huge tubers, is at times an exception to this 

 rule ; small tubers follow the rule. The perennating bodies of N. flava 

 (doubtless also of N. mexicana] begin the growth of each bud with a few 

 water-leaves, and the other Castalia species produce them either in late 

 fall or early spring, or both. These members also lose their floating 

 leaves and produce only water-leaves in unfavorable conditions " of culture, 



1 Deja visibles, mais tres-petits sur la jeune feuille, pourvus d'un axe en forme de tubercule, mais 

 avec des feuilles encore tres-rudimentaires, sur la feuille adulte et pleine de vie, ils restent presque 

 stationnaires tant que la feuille tient a son pied nourricier. Qu'on detache artificiellement cet organe 

 ou qu'il s'isole spontanement par la decomposition de son petiole, aussi tot le bourgeon pousse 

 des racines, developpe rapidement ses feuilles et semble se hater de vivre d'une vie indepen- 

 dante. (Flore des Serres, 8: 285.) 



'Bonnier (1890) found in several lakes of the Alps shoots of N. alba without floating leaves, 

 but with an unusually large number of submerged leaves, "as is often seen in streams with rapid 

 current." 



