— 77 
^^Invertebrate Animah. — For various reasons compara- 
tively few of these are exhibited in the Aquarium. In the 
first place it is difficult to keep them in the same tanks with 
fish, to the rapacity of which they soon fall victims, and 
secondly, none of them thrive particularly well under the 
artificial conditions to which they are subjected. In the 
small floor aquaria will, from time to time, be found cuttle- 
fish, hermit-crabs, sea-anemones, and other invertebrates 
which are described in special labels. Certain of the larger 
Crustacea are occasionally exhibited in tank 2, and of these 
some beautiful forms occur on the Madras coast, notably the 
large lobster (^Pannlirus)^ and brightly coloured swimming- 
crabs {Neptunus) . The South Indian sea-anemones, shown 
in floor aquarium E, do not compare favourably with the 
large showy specimens which form such an attractive display 
in European aquaria. 
“ Fresh Water Animals. — The place taken by these in the 
Aquarium is an altogether secondary one, and, as already 
remarked, all the large tanks contain salt water. In spite of 
this fact there will be seen in tank 3 a number of specimens 
of the perch-like fish, Etroplus suratensis^ where they have 
lived and flourished for upwards of two years, and there 
are other local fish, which appear to live equally well in fresh 
or in salt water. In the fresh-water tanks aeration is secured 
by growing pond weeds, which during the daytime liberate 
a sufficient quantity of oxygen to meet the requirements of 
the animal inmates. 
“ On account of curious incompatibilities of temper, it has 
been found impossible to arrange the bony fish according to 
any scientific classification, for in several instances experience 
has shown that even closely related species will not dwell 
amicably together. Some specimens exhibit such a pugna- 
cious disposition that they have to be removed from the 
Aquarium altogether. In a few cases, for the above reason, 
single individuals have had to be removed from the compa- 
nionship of the other members of their species, and placed 
in a separate tank. It would of course be possible to obviate 
this were the number of exhibited species strictly limited, 
but by so doing it is felt that a good deal of the attractive- 
ness furnished by a large variety of fish would also be lost. 
