32 THE FRESH-WATER AQUARIUM. 
be contemplated without pleasure. J. triscula is a very 
pretty kind, common in the neighbourhood of London. 
The sweet-scented Rush, members of the Alisma tribe, 
the noble Sagittaria of six species, the Hornwort (Cerato- 
phyllum) of two species, and for more delicate purposes, 
Chara and Nitella may be recommended as suitable addi- 
tions to the botanical department of the Aquarium. 
CHAPTER V. 
FISHES FOR THE AQUARIUM. 
I sway here give the names and a few particulars of the 
history of the fishes that are most suitable for the aquarium, 
reserving my notes on the grouping and general stocking 
for a subsequent chapter. It is to the interesting family 
of Cyprinide we are to look for our chief supplies. This 
tribe of fishes belongs to the great division of Malacop- 
terygii, or those having their fin-membranes supported by 
flexible rays, which are either pointed or branched, or 
both. 
Cyprinus carpio, the British carp, is a handsome fish, 
differing slightly in structure from the Prussian and gold 
carp; yet, in general outline, preserving the true carp 
type—plumpness of body, iridescence of colour, and ease 
of movement in the water. This carp has a moderately- 
developed pair of moustachios, in the form of a barbule, at 
the upper part of each corner of the mouth, and a second 
one above it, on each side. Like the rest of its kindred, 
it is very tenacious of life, and does not quickly suffer 
from exhaustion of oxygen. It is an old fish, so to speak, 
