[7] NUTEITIVE VALUE OF FISH AND INVERTEBRATES. 



Sum of Protem (N X 6.25) ether extract, ash and water in flesh offish. 



439 



A more satisfactory way of getting- at this matter is the usual one of 

 dividing the total amount of nitrogenous matter by the amount of nitro- 

 gen and obtaining as quotient what may be termed #e nitrogen factor 

 of the protein, the amount of protein being simply the sum of the ni- 

 trogenous compounds, determined either directly, or, as in the present 

 case, by difference. If the protein contains 16 per cent, of nitrogen the 

 nitrogen factor is 100-4-16 = 6.25. If the percentage of nitrogen is 

 larger, the nitrogen factor is smaller, and vice versa. 



I have improved the occasion of analyzing the flesh of other animals 

 referred to in the introduction to this article to compute the nitrogen 

 factors for protein in those as well as in the fish-. Some of the results 

 are stated in the following tahtle. Only the fresh (not the preserved) 

 ^sh are included. 



