ySo BULLETIN OF THE BUREAU OF FISHERIES. 



which eggs of widely different species may be hatched and reared and by which 

 the unidentified fry caught at large may be reared under observation will be 

 able, we hope, to furnish the necessary material for the solution of this general 

 problem. 



APPLICATION IN TRANSPORTATION OF LIVE FISHES. 



In our opinion the essential principle upon which this method of fish culture 

 is based will be found of value in solving the prol)lem of the transportation of 

 live fishes and, moreover, the method and even a portion of the apparatus 

 can be modified and adapted so as to carry this principle into effect. The 

 principle is, briefly, to provide at the start native "unmodified" water; to 

 maintain a proper temperature and density, and in some cases current; to 

 secure the continuous "respiration" of the water, including the egress of waste 

 gases of the metabolism of contained fishes and often of bacteria as well as the 

 access of oxygen, and to avoid contact with injurious metallic substances. 



To carry into effect this principle we propose the following method : To use 

 for transportation an iron tank enameled on the inside with a vitreous substance 

 in order to prevent contact of the water with the metal; to use only water 

 dipped from the water in which the animals have been living, in order to insure 

 its proper constitution; to surround the tank with a jacket into which ice or 

 warm water can be put to control the temperature (for many animals, at any 

 rate, both among fishes and invertebrates, we have found by experience that a 

 low temperature is a very important factor in maintaining life when the animals 

 are crowded into a small amount of unrenewed water) ; to provide both the 

 current and the continuous respiration by installing a propeller device of 

 enameled iron kept in motion by means of a spring motor. 



