236 The Waterliues. 



estates and botanic gardens of England with the introduction of N. odorata 

 in 1786. From that time until 181 2 several species were brought to 

 English gardens. Then there was a period of inactivity until the appear- 

 ance of Victoria about 1840 aroused great interest in aquatics. From 

 1850 to i860 this wave reached its maximum, when Planchon, Lehmann, 

 and Hooker described several species, and Caspary began his immortal 

 work on the genus. There followed a lull until near 1880. Probably 

 N. zanzibariensis served to bring its congeners before the public again. 

 Another wave of waterlily culture set in, which probably has not yet 

 reached its maximum. So magnificent are the results recently achieved, 

 and of so lasting a nature, that this branch of gardening is likely to be of 

 importance as long as flowers are grown for the beautifying of public or 

 private grounds. 



For cultural purposes we may divide the genus into two groups the 

 hardy and the tender varieties. In the first group Castalia stands alone. 

 All others are tender in our climate. In the Botanical Magazine and 

 Flore des Serres brief cultural directions are given for each species de- 

 scribed ; these are almost wholly intended for tender varieties when grown 

 under glass. But since the extended culture of these plants can only be 

 carried on where the climate will admit of their being for three months at 

 least out of doors, we shall speak only of the latter condition. Out-door 

 culture of tropical forms is of very recent date. So recently as 1891 Herr 

 Borsig's water garden in Berlin was noted as of especial interest. He 

 warmed the pond with waste hot water from his factory. Mr. Vilmorin 

 described the place in Revue Horticole, and the article was reproduced in 

 translation in the London Garden, and in Garden and Forest (1891, p. 375). 

 In Garden and Forest for 1888 (pp. 241-242) cultivation of waterlilies in 

 shallow ponds is urged as both possible and desirable in the eastern United 

 States. In the garden trade the hardy species were slower than the 

 tender ones in getting recognition. Gardeners' Chronicle in 1848 informs 

 a correspondent concerning N. alba that " the roots of these things may 

 sometimes be had in the nurseries, but they are not usually kept." In 

 1849, however, it is stated that N. rubra-, caerulea, stellata, and ampla may 

 "be had from any of the large nurserymen." Vick's Catalogue for 1883 

 mentions only A^. odorata. At present sixty-four varieties are entered in 

 the catalogue of one of the leading American dealers. 



The care of them is very simple. The pond or tank may be only a 

 large bucket or a half-barrel ; in such accommodations N. tetragona, N. t. 

 helvola, N. marliacea chromatella, or even N. caerulea, will get along and 



