450 BULLETIN OF THH UNITED STATES FISH COMMISSION. 



This mixture, witli tlie addition of 10 pounds of cooliiug--salt and 

 water, is kneaded into a stiff, tougli paste, and by means of a sausage- 

 squirt, with an opening tbe size of a thick lead-pencil, laid out on 

 boards which are sprinkled with flour, and there allowed to dry. It 

 is jiossible that an addition of ground cockchafers will make the food 

 more enticing for the fish and it is worth while to try it. In that case 

 one might use 50 pounds of ground meat and 15 pounds of cockchafers. 

 The corn might be replaced by peas or field beans, which are cheaper 

 and much more nutritious, and the food would doubtless be imjjroved 

 thereby. 



2. For the food-flour {F utter melil) take — 



To every 100 pounds of the mixture as much as 10 pounds of common 

 salt should be added. 



If we examine the quality of the articles of food analyzed above, as 

 to their chemical composition, and especially as to the quantity of par- 

 ticularly valuable substances contained in them, we arrive at the fol- 

 lowing result : 



There are contained in — 



Proteine 



Fat 



Hydrates of carbon 



A.— Cylin- 

 der-food. 



Per ci-nt. 

 53 

 10 

 16 



:B.— Feed- 

 flour. 



Per cent. 



35 

 12 

 30 



According to Dr. E. Wein, the practical value is as follows : 



A. [ (53 + 10) X 16] + [10 X 3.2J = 10 marks, 59 pfennigs [$2.52]. 



B. [ (35 + 12) X 16] -f [30 X 3.2] = S marks, 48 pfennigs [|2.01]. 

 But, as was stated above, when we buy the ingredients we must pay 



12.65 marks [$3.01] for cylinder-food, and 0.90 [$2.33] for feed-flour. 

 We refer here, of course, to the best quality, for an inferior article may 

 be bought from dealers for 22 marks [$5.23]. Under these circumstances 

 there is of course no xnospect of making it pay to raise fish on these sub- 

 stances. 



In food suitable for fish-culture one Icoks, of course, for a certain per- 

 centage of albuminous matter, fat, and hydrates of carbon j but in using 



