AQUARIUM. 



205 



aquatic plants. None of fresh water is 

 strictly aquatic and always has its foli- 

 age submerged, as during the flowering 

 season all develop either surface-float- 

 ing or emersed leaves and blossoms; 

 but those whose habit is to remain sub- 

 merged at other times are the best 

 liberators of oxygen ; and, except for 

 ornamental purposes, should be given 

 the preference in the aquarium. The 

 more generally distributed or easily 

 obtainable of these, in the order in 

 which they best fulfill their purpose, 

 are the ribbon-leaved arrowheads, 

 Sagittaria iiatans and 5". sinensis; the 

 watefshield or fanworth, Cabomba caro- 

 liniana and C. rosaefolia; the ditchmoss, 

 Anacharis canadensis and the cultivated 

 A. canadensis gigdntea; the eel or tape- 

 grass, Vallisneria spiralis; the water-mil- 

 foil, Myriophyllum spicatum and the near- 

 ly related parrot's feather or Proserpin- 

 aca. .1/. proserpinacoides ; the swamp- 

 loosestrife, Ludwigia palustris and L. 

 glandulosa, together with the handsomest 

 tropical species L. mulerttii; the stone- 

 worts, Nitella gracilis and Chara gyvn- 

 nopus; and the less desirable but 

 ornamental hornwort (Ccratophylittm) , 

 willowmoss (Fontinalis), riverweed 

 (Pota)iiogeton) , starwort ( Callitrichc) , 

 bladderwort (Utricularia) , and many 

 other partially submerged or floating 

 plants which add beauty and attraction 

 to the aquarium. These will be more 

 fully described in a later article. 



Next to plants scavengers should have 

 the attention of the aquariist, as success 

 largely depends upon their efficiency in 

 disposing of the refuse and offal. 



The scavengers of the freshwater 

 aquarium are tadpoles, snails and mus- 

 sels. Frog tadpoles retain their larval 

 form longer than toads ; when either 

 develop legs and assume the adult form 

 they subsist on live food and are no 

 longer of use in the aquarium. Of the 

 freshwater snails four species best serve 

 as scavengers, the ramshorn snail, Plan- 

 orbis trivolvis and P. companulatits, the 

 Potomac snail, Viviparus viri par us, the 

 transparent African snail, Lynmaae auri- 

 cularia and the Japanese snail, V. mal- 

 leatus, each differing somewhat in pre- 

 ferred diet. If these cannot be obtained 

 any other freshwater snails which will 

 not destroy the plants may be introduced. 



Of the freshwater mussels any taken 

 from Stillwater will serve, but those of 

 the genera Lampsilus and Margaritina 

 survive the longest in the aquarium. 



Sand, small pebbles and sod soil are 

 also required, into which to root the 

 plants. Sea sand, the smaller pebbles 

 known as "grit" and clean turf taken im- 

 mediately under the roots of lawn grass 

 are generally used. 



These materials at hand, only the fishes 

 still remain to be described and this will 

 be done later ; it is now in order to 

 arrange the aquarium, which should be 

 established a week or two before fishes 

 are introduced. 



The inside of the aquarium should be 

 cleaned with whiting for the glass and 

 salt water for the slate bottom, thorough- 

 ly rinsed and set into position. Sagit- 

 taria, Cabomba, Anacharis, Myriophyl- 

 lum. Proserpinaca and Nitella may be 

 set directly into the sand or pebbles, but 

 Vallisneria, Ludwigia and Potamogeton 

 thrive best when planted in shallow pots 

 or dishes into which turf is placed and 

 covered with pebbles. A layer of sand 

 two-inches thick should first be put into 

 the aquarium and then the plants neatlv 

 set into it, arranging them on the three 

 si iles towards the light and leaving an 

 open space on the inner side towards the 

 room, for the living inmates to disport 

 themselves. Then sand, pots etc. should 

 be covered with an inch thickness of 

 grit, placed so that the side facing the 

 room is of slightly lower level than the 

 others, that the humus (refuse) may 

 there collect for easy cleaning. 



When the plants are arranged, they 

 should be covered with wrapping paper 

 upon which the water may be slowly 

 poured so as not to disturb the contents 

 and then the aquarium filled to the top. 

 Tadooles, snails and mussels should be 

 put in at once and the aquarium left un- 

 disturbed until the water is clear, the 

 plants rooted and growing, the molluscs 

 and tad"oVs acclimated and active, and 

 then only the fishes introduced. 



For a t, 2 by 16 by 16 inches aquarium, 

 having a capacity of 32 gallons of water, 

 six tadpoles, ten or twelve snails and two 

 mussels would be required ; for smaller 

 aquaria proportionate^ less. 



(Continued in our following number). 



