AQ.UATIC PLANTS. 



blotch at the base of each petal. They have been 

 compared to some species of Culochortus. It has 

 developed verj^ finely, producing- a profusion of 

 flowers, in one of the mud beds in which the 

 ^N'elumbiums are grown at Kew. It is raised 

 easily from seeds. Native of South America. 

 Alismacccc. 



Salvinia natans. — This is an extremely pretty and 

 interesting small aquatic, which floats on the wutei', 



ovate in shape, and provided with a swollen stalk. 

 The flowers are inconspicuous. It produces curiously 

 horned fruits, which are supposed to resemble the 

 Caltrops of ancient warfare. They are the Jesuit's 

 Nuts of Venice, and are called " Chataigne d'Eau" by 

 the French. This and other species are used for 

 food, the nuts being ground into flour. In cultiva- 

 tion, good seeds are not produced, and they require to 

 be imported in damp moss. It may be grown in a 



The Lattice Plant {Ouvirandra fenpstralis). 



and can be grown in any small vessel with mud in 

 the bottom. The leaves are oval, bright green, 

 thickly set on the upper surface with warts and 

 bristles. There are numerous pill-like fruits on the 

 dissected leaves below the rhizome ; there are no 

 true roots, but these leaves resemble them, and serve 

 the same purpose. The plant is annual, and the mud 

 over which it grows must be preserved, as it contains 

 the spores which produce a new crop the next season. 

 It is figured in the Gardeners^ Chronicle, vol. xv., 

 N.S., p. 466. Native of the South of Europe. 

 Marsileaceee. 



Trapa natans (the Water-caltrops). — An interesting 

 annual with pretty rosettes of toothed leaves, broadly- 



tub with soil in the bottom, and in warm water out 

 of doors it grows well. The species above mentioned 

 is European. Others, as the twb-hqmed T. bicornis, 

 the " Ling" of the Chinese, might be introduced. Il- 

 lustrated in The Garden, vol. xxiv., p. 557. Ona- 

 grariece. 



Trianca = Limnohlnm. 



VaUlsneria spiralis. — This is specially suited foi 

 smaU aquaria. It has long narroAv grass-like leaves, 

 and is interesting by the curious manner of its 

 fertilisation, and by its convenient^ showing inter- 

 cellular circulation under the microscope. It must 

 be submerged, and it grows with great facilitj', but 

 the male plant appears more delicate than the 



