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 aquaruist, 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 Vallisneria next following, all hardy and easily pro- 
pagated; while in further order of their utility, 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 Alismacee; Cabomba to the Nympheacez; Vallisneria to the Vallis- 
neriaceae; Myriophyllum to the Halorrhagidacee; Ludwigia to the 
Onagracee; Nitella and Chara to the Characee; Anacharis to the Vallis- 
neriacee; Ceratophyllum to the Ceratophyllacee; Hippuris to the 
Halorrhagidacee; Fontinalis to the Musci; Potamogeton to the 
Naiadacee; Callitriche to the Callitrichaceee; Utricularia to the Lentibu- 
lacee; Proserpinaca to the Halorrhagidacee, and Heterania and Hottonia 
to the Primulacee. 
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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