286 BULLETIN OF THE UNITED STATES FISH COMMISSION. 
In a previous paper* the writer gave suggestions regarding the estab- 
lishment of homes for aquatic and amphibious animals, but more es- 
pecially adapted to those of smaller size. Those suggestions were made 
on the test of actual experiment. The question arises whether the 
same methods on a scale of magnitude adapted to the largest animals 
would not produce equally satisfactory results. Undoubtedly by far 
the greater cost of maintenance of large aquaria and zoological collec- 
tions is due to excessive mortality. The laws which apply to the herd- 
ing or imprisonment of men apply with greater force to the lower ani- 
mals, which are less amenable to artificial conditions. Fishes confined 
in small bodies of water are infested with parasites, which do not trouble 
them in ponds and streams where they have mud, sand, masses of 
plants and rocks, by means of which they can rid themselves of such 
pests. Fishes and reptiles, and I doubt not other animals as well, are 
also, undoubtedly subject to diseases analogous to scurvy and others of 
that nature produced in man by close confinement and consequent im- 
purity of surroundings. 
There is another aspect of the case, that of the effects of imprisonment 
upon the mind. Most persons are familiar with the fact from personal 
observation that it is almost impossible to confine many of our adult 
wild birds in cages; as they will refuse to eat and will speedily die 
of starvation, or will beat themselves to death on the wires of their 
cages. Those who have had exeperience in the care of fishes will have 
noticed the same results in the cases of many kinds of them. It is im- 
possible for an observing person at all experienced in the care of ani- 
mals of whatever nature not to concede to them the emotions pleasur- 
able or unpleasurable common to mankind regarding surroundings. 
Nothing can be more depressing to the lover of nature than the for- 
lorn and dejected appearance of the birds and beasts of fiercer nature 
as they appear in the limited areas and unnatural surroundings allot- 
ted to them in zoological gardens. 
Prof. H. C. Chapman states as a result of his examinations of carniv- 
orous animals which have died in captivity, that most of them die of 
heart disease. 
From this benevolent view alone, therefore, this question is one well 
worthy of consideration. Surely, if the dumb brutes contribute to our 
pleasure or benefit, we may well afford to consider the possibility of 
making them measurably contented and happy. 
With this idea in view I offer the following suggestion for the con- 
sideration of those interested in the establishment of large aquaria, 
hoping for further development through interchange of ideas. 
The plan or principle herein suggested might be termed not inaptly 
Pond- Aquaria, it being essentially a combination of the pond and the 
* The Aqua-Vivarium as an Aid to Biological Research. Report U. S. Fish Commis- 
sion, 1883. 
