522 REPORT OF COMMISSIONER OF FISIT AND FISHERIES. 
li ving state. This may be made a most important display supplementary 
to the exhibits in the zoological garden to be established in Washington 
under the direction of the Smithsonian Institution. The fresh-water and 
marine aquaria, the great national museums of art, science, medicine, 
and anatomy, the great libraries, botanical and zoological gardens situ- 
ated so near together, will thus doubtless become centers of great public 
interest and afford a most useful educational influence in Washington. 
The adaptation of an aquarium for the convenience of the artist in 
delineating the fishes has also been devised by the Commissioner. A 
movable diaphragm of glass is suspended So as to make it possible to 
restrict at will the space in which a live fish is confined while being 
sketched. This serves to keep the animal quiet in a narrow space, and 
enables the artist to work more confidently in catching details of form 
and color. The same device will be used in conducting experiments in 
photographing the living fishes in the water. 
It is most earnestly to be hoped that a continuance of the liberal 
cooperation of Congress with the Fish Commission may be maintained, 
in order that the present Commissioner, Prof. Marshall McDonald, may 
be enabled to further develop the interests of practical fish-culture in 
America. The policy of the Commissioner is simply to continue in the 
line of work originally proposed by Professor Baird, and to call to his 
aid, in the work of elucidating the economico-biological problems which 
call for answers from time to time, the leading biologists of the country. 
This makes the maintenance of a great seaside laboratory near the fish- 
ing interests of the country a necessity, if the fullest significance is to 
be given to the economical work which still remains to be carried out. 
The marine organisms which man uses as his food prey upon each other 
and upon such living things as are not directly available as food for man. 
It thus comes about that when the life-history of any form used as food 
i£ to be fully known, the habits, habitats, or natural history of hundreds 
of forms which have no direct relation to man’s wants must also be 
studied. This can nowhere be so well done as in a properly equipped 
and maintained seaside laboratory or zoological station, which should 
aim to achieve the preeminence so deservedly attained by the world- 
famous establishment founded by Professor Dohrn at Naples. Dr. 
Dohrn, besides devoting a large private fortune to organizing his estab- 
lishment, has had the assistance of the German and Italian Govern- 
ments, and of that most enlightened and liberal-minded prince, the late 
Frederick III, Emperor of Germany, while several learned societies and 
institutions have also rendered him other important aid. If individual 
enterprise, aided by some of the governments, princes, and academies 
ot Europe, can take pride in pursuing biological investigation for its 
own sake and quite irrespective of any economic bearings it may have, 
it is surely not too much to expect this great country to support re- 
searches which have the most direct and immediate bearing upon the 
food-supply of a nation of fifty millions of people. 
