78 
RESERVOIRS IX CANTON. 
derm, witlx a lean body, long legs, a 'wedge-like 
head, a bristling crest, an inquisitive nose, a wicked, 
vigilant eye, a straight tufted tail, and a shrill, 
angiy voice. 
The numerous ponds within the walls of the city 
of Canton are intended as reservoirs of water iii 
case of fire. They are by no means filthy or 
muddy receptacles, but resemble in beauty and 
cleanliness the parlour ponds and aquatic vivaria 
of our gardens on a large scale. The surface is 
covered with a mass of bright green fioating vege- 
tation; while the margins are fringed with crisp and 
juicy esculent vegetables. The water below teems 
with carp, dace, and other fish which live upon the 
fresh-water mollusks, these in their turn feeding 
on the superabundant vegetable matter. The pond 
shell-fish consist of a species of Sphserium, and one 
or two kinds of Vivipara, or Paludina. One of the 
fish, a species of Ophiocephalus, has no teeth in the 
jaws, but the pharynx is provided with a pah of 
j)owerful supplementary maxillae armed with formid- 
able serrated teeth, Avhich play against a hard, 
