REPORT OF COMMISSIONERS OF INLAND FISHERIES. 87 



in the water even when artificial food heavier than water is used. 

 When, on the other hand, a pelagic live food is used, it is also, of 

 course, readily available, because it is kept in motion and suspended. 

 The important problem of the distribution of food for pelagic forms 

 is solved by this method in a most satisfactory manner. 



ADAPTABILITY OF THE METHOD. 



Before describing the apparatus as at present installed at our 

 station where is it applied to the hatching and rearing of young fishes 

 and invertebrates, a word should be said to indicate its general 

 adaptability to various requirements. In any protected body of 

 water, whether river, lake, pond, or in the ocean itself, the apparatus 

 can be quickly and cheaply installed. For experimental work the 

 containing cars may be small. Dr. V. E. Emmel, by use of this 

 method, succeeded for the first time in the difficult task of making 

 mutilated lobsters of the first stage live to regenerate their appendages. 

 His apparatus consisted of an ordinary "paper" bucket provided 

 with screens and the apparatus for keeping the water in motion. On 

 the other extreme the units in our regular installation at Wickford, 

 are square boxes measuring 10 feet on a side and 4 feet in depth, 

 and having a capacity of approxim^ately 12,000 liters (figs. 4, 6, 17). 

 The capacity of a plant of this sort is capable of unlimited extension by 

 the addition of units. At present the plant at Wickford has a capa- 

 city of 24 units of the size mentioned. The method is capable of 

 application to aquatic animals, fresh water or marine, varying in size 

 from those literally microscopic to those of a foot or more in length. 

 We do not foresee that there are any strictly aquatic animals the 

 requirements of whose young may not be fulfilled by means of this 

 method. 



We have developed and applied the method mainly in connection 

 with the hatching and rearing of larval lobsters, but we may assert, 

 without fear of contradiction by anyone familiar with the rearing of 

 lobster fry, that we have done this not because of the comparative 



