124 REPORT OF COMMISSIONERS OF INLAND FISHERIES. 



two weeks during which the fry usually remain in one car, are objec- 

 tions to its continued use. 



In a careful series of food experiments at our station Doctor Emmel 

 decided, after using clam, liver, beef, and some other foods, that 

 chopped raw beef gave best results, all points considered. However, 

 with a large quantity of fry to feed, it was found to be difficult to 

 prepare cheap raw beef finely enough divided for practical use. 

 Boiled beef coarsely ground (Hamburg steak), boiled, and ground 

 again, and then beaten up in water with an egg beater, was used with 

 gratifying results during the latter part of the present season. It 

 has the advantage that it is easily prepared, even though the cheapest 

 and toughest is chosen, and that when prepared in this way the 

 pieces are small and correspondingly numerous. The particles are 

 readily held in suspension, and when put into the water little by 

 little with a long-handled scoop or shaken through a fine netting, 

 (Fig. 6) , they form a cloud of light-colored and easily visible particles 

 and are distributed so evenly that they are available at every feeding 

 to all the thousands of individuals in the car. Prepared in this man- 

 ner, the beef leaves scarcely any residue; most of the uneaten finely- 

 divided pieces are carried out gradually through the windows. In 

 its use one prime precaution must be taken; it must not be allowed 

 to become stale or previously soaked with water. Care should also be 

 taken to put the raw beef into boiling water and so to coagulate and 

 conserve its albumens. 



For the reason alluded to, namely, to keep the larva? not only well- 

 fed but constantly satiated, thereby preventing cannibalism, it is 

 necessary to feed them often, and we adopted the schedule of feeding 

 every two hours through the night and day. Even with the best 

 possible food — and this has yet to be discovered — there is a "knack" 

 in feeding, and it is one of the points in the care of the fry which 

 repays careful attention, for, besides having the advantages just 

 mentioned, adequate food undoubtedly increases the rate of growth 

 and shortens the larval period. 



