29 THE FRESH-WATER AQUARIUM. 
pleting the collection by the introduction of fishes. 
Where a beginner has sufficient patience to wait, this is 
very advisable, because the whole gets well settled, the 
plants start into growth, and the water gets softened and 
charged with oxygen. But this plan is not the only one 
that may be followed, and if well-washed pebbles be used 
instead of mould, as I have advised, the fishes may be 
introduced the same day as the plants are inserted, by 
CALLITRICHE. 
first taking care that you insert plenty of large healthy 
plants, and then throw on the top as much of the brook 
starwort—Callitriche autumnalis—as will cover the 
whole. I lately stocked two tanks in this way, and per- 
formed the whole in less than two hours, forming the — 
bottom, planting the vegetation, and adding the fish— 
perch, tench, Prussian and British carp, roach, minnows, 
