AQUATIC PLANTS 



A number of generally procurable aquatic plants thrive at all seasons 

 under the unnatural conditions of the household aquarium, and not only 

 add to its beauty by their graceful forms and fine colors but also fulfill the 

 imperative requirement of properly aerating or oxygenating the water, 

 whereby supplying to the animal inmates the air necessary to their exist- 

 ence. These plants are sought by the aquariist, and, as they belong to 

 different genera, they will be described not in their botanical order but in 

 the order in which they most effectually serve these purposes. Those 

 which grow rapidly and for the greater part of the year have their foliage 

 submerged, taking the required carbon and nitrogen from the soil and 

 water, also liberate the greatest amount of oxygen to remain in available 

 form in the water. Experiment has proven that the ribbon-leaved 

 Sagittarias are in every way the best aquarium plants, with Cabomba 

 Giant Anacharis and Valiisneria next following, all hardy and easily pro- 

 pagated; While in further order of their utiHty, satisfactory growth and 

 endurance are Myriophyllum, Nitella and Anacharis; Ludwigia, Cerato- 

 phyllum, Hippuris, Fontinalis and Potamogeton; Callitriche, Utricularia, 

 Proserpinaca, Heterenia and Hottonia; and finally the Lilies, Water- 

 poppies and other aquatic and semi-aquatic plants either not entirely sub- 

 merged or floating. 



The orders to which the aquarium plants belong are: — Sagittaria to 

 the Alismacese; Cabomba to the Nympheacese; Valiisneria to the Vallis- 

 neriaceae; Myriophyllum to the Halorrhagidacese; Ludwigia to the 

 Onagraceae; Nitella and Chara to the Characeas; Anacharis to the Vallis- 

 neriaceas; Ceratophyllum to the Ceratophyllaceae; Hippuristo the 

 Halorrhagidaceae; Fontinalis to the Musci; Potamogeton to the 

 Naiadaceae; Callitriche to the Callitrichaceae; Utricularia to the Lentibu- 

 laceae; Proserpinaca to the Halorrhagidaceae, and Heterania and Hottonia 

 to the Primulaceae. 



It may be noted that when it is the habit of an aquatic plant to carry 

 part of its foliage above the surface of the, water, better results will be ob- 

 tained by rooting it in soil instead of in the sand or pebbles and covering 

 the surface with a layer of pebbles; for, though many will thrive either 

 rooted in the pebbles or floating unattached, as they derive nearly all of 

 their nourishment from the water, when set in shallow dishes with soil 

 they are more likely to root, thrive and develop satisfactorily in the 

 aquarium. 



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