ted lying on the surface of the water. The
fish have been lively, bright in colour, and appear very healthy; and
the snails also--judging from the enormous quantities of gelatinous
masses of eggs which they have deposited on all parts of the receiver,
as well as on the fragments of stone--appear to thrive wonderfully,
affording a large quantity of food to the fish in the form of the
young snails, which are devoured as soon as they exhibit signs of
vitality and locomotion, and before their shell has become hardened.'

In remarking upon the result of his experiments, Mr Warington
observes: 'Thus we have that admirable balance sustained between the
animal and vegetable kingdoms, and that in a liquid element. The fish,
in its respiration, consumes the oxygen held in solution by the water
as atmospheric air, furnishes carbonic acid, feeds on the insects and
young snails, and excretes material well adapted as a rich food to the
plant, and well fitted for its luxuriant growth. The plant, by its
respiration, consumes the carbonic acid produced by the fish,
appropriating the carbon to the construction of its tissues and
fibres, and liberates the oxygen in its gaseous state to sustain the
healthy functions of the animal life; at the same time that it feeds
on the rejected matter, which has fulfilled its purposes in the
nourishment of the fish and snail, and preserves the water constantly
in a clean and healthy condition. While the slimy snail, finding its
proper nutriment in the decomposing vegetable matter and minute
confervoid growth, prevents their accumulation by removing them; and
by its vital powers converts what would otherwise act as a poison into
a rich and fruitful nutriment, again to constitute a pabulum for the
vegetable growth, while it also acts the important part of a purveyor
to its finny neighbours.'[5] This perfect adjustment in the economy of
the animal and vegetable kingdoms, whereby the vital functions of each
are permanently maintained, is one of the most beautiful phenomena of
organic nature.

The Parlour Aquarium affords valuable, we might say invaluable,
facilities to the naturalist in the prosecution of his researches. The
botanist can now conveniently watch the development of aquatic plants
under conditions _not_ unnatural, throughout the entire period of
their existence, from their germination to the production of flowers
and the perfection of seeds; and we are in hopes that much of the
obscurity tha