HARDY HYBRID WATER-LILIES. 



293 



they only prevent the roots and rhizomes from meeting, without 

 preventing the leaves from intermingling on the surface. Two 

 feet down from the bottom of the kerb-stone is enough for the 

 depth of the basins. The outside walls ought to be decidedly 

 slanted outward, so as to run less risk of their being damaged by 

 hard frosts and the pressure of the ice, which would certainly 

 happen if they were built straight up. 



A bed of earth six inches deep on the bottom of the basins will 

 be amply sufficient for the culture of Water-lilies and for most 

 other aquatic plants : it ought to be as free as possible from 

 gravel and stones. The best kind of earth is heavyish loam 

 from the garden or meadow, but earth composed of leaf-mould 

 and alluvial soil is also very suitable. One can also make a 

 mixture of them, but it is better not to put with them any fresh 

 manure which is still undergoing fermentation. 



As regards the choice of water, that which comes from a 

 stream or river is to be preferred, though that from wells will 

 do. When the water is taken from running springs it 

 ought in summer to be turned off from the basins, so as to keep 

 the temperature of the water the same as that of the air ; for it 

 is essential to remember that Nymphn?as thrive best in stagnant 

 water, or at least in a very gentle current. 



In stocking a basin with Water-lilies the object should be to 

 obtain by a harmonious combination and sequence of shades and 

 colours a generally dazzling effect, and for that purpose plants 

 with high stalks should be avoided, as that would destroy the 

 general view. It is necessary also to suppress Confervae and those 

 Mosses which are too compact, and certain under-water plants 

 which are clogging and clinging, such as Chara, Cabomba, 

 Yallisneria. Elodea, Potamogeton, &c, which live at the expense 

 of the Water-lilies without adding anything to the ornament of 

 the picture. Nevertheless it is as w r ell to except from this pro- 

 scription Tropas natans and T. verbanensis, Stratiotes aloides, 

 and Aponogeton, which are quite worthy of being admitted into 

 the society of Water-lilies. 



The Tropas display gracefully upon the surface of the water 

 their triangular leaves, with swollen petioles, disposed in rosette- 

 like form, those of T. verbanensis being larger and particularly 

 distinguishable by the stalks and veins of the leaves being of a 

 pretty red colouf. The fruits of these two annual kinds, known by 



