198 THE FERN PARADISE. 
reverse it, fitting its knobs into a stand, we have 
at once, if we fill it with water and introduce 
some rocks and fish and aquatic plants, a minia¬ 
ture aquarium, and one adapted for transformation 
by the simplest of simple contrivances (page 197) 
into a miniature fernery. We have merely, on 
the upper side of the rockery required for the 
comfort and convenience of the little fish we 
propose to put into our bell-glass aquarium, to 
have a hollow bed above water-level, into which 
we can put some Fern soil. We can then plant a 
Fern or Ferns in the little extemporized island, 
and the situation will at once be found to be most 
congenial both to the Ferns and to the fish. 
The methods, indeed, are numerous by which 
Ferns may be brought into association with fish 
in aquaria. The object must always be to copy 
Nature as nearly as possible. The reversed bell- 
glass represents in miniature, as we have seen, a 
lake or pond, with an islet in its centre; and in 
this miniature structure the rocks may be built 
up on its lower side so as to afford the holes and 
corners in which, in a natural piece of water, fish 
love to hide, whilst the upper side should be made 
