The Balanced Aquarium and the Snailery 



growing, the year around; and it is one of the few best aerators 

 of water. 



The Milfoil (Myriophyllum spicatum) ranks next. Its plume 

 is rounded and full. It has the fault of dying away at intervals. 



The Hornwort (Ceratophyllum demersum) resembles the mil- 

 foils, and it lasts longer. 



The Eel-grass or Tape Grass {Valisneria spiralis) has narrow 

 flat leaves, like green ribbons. It is an intensely interesting study, 

 as well as a valuable tenant of the aquarium. It takes root 

 easily, and throws up vigorous new shoots. At blooming time 

 the solitary buds of the fertile plants rise to the surface on slender 

 coiled stems. The sterile flowers tumble off of their short stems 

 and rise to the surface. Floating about, these pollen-bearers 

 brush against the pistils of the fertile flowers, thus effecting their 

 pollination. Thereupon the coiled stems draw down the flowers 

 which mature, under water, the seed thus set. The sterile flowers 

 wither. 



Water Thyme {Anacharis Canadensis) is one of the most 

 vigorous of aquarium plants, and is easily obtained in many 

 regions, where it chokes streams and canals. 



Pond weed {Potamogeton densum) has a fern-like leaf, and 

 grows well in the tank. Though not so easily obtained as the 

 Parrot's Feather, a close relative which florists grow, it is much 

 more desirable. The latter exhales very little oxygen, though it 

 has a dense, showy plume. 



The Stoneworts, Nitella and Chara, bear tufts of silky hairs 

 that sway most gracefully when a tadpole or a fish flips his tail 

 near by. 



Water-silk (Spirogyra) is a fine network of green threads, 

 which floats, and is often mistaken for "scum." A hand-glass 

 brings out its beauty. 



Duckweeds (Lemna) float like pale threads, their minute 

 green leaves flattened on the surface of the water. Many tiny 

 snails and other creatures harbour and forage on them. 



Riccia, which looks like a sprinkling of green sawdust, is a 

 good plant. 



Conferva is the botanical name of several kinds of alga;, 

 microscopic plants, which appear as a green film lining your 

 tank, especially if it is in a well-lighted place. Fairy ropes of it 

 festoon the walls and connect the plumes of the plants. This is 



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