APPENDIX. 



The following is a list of the larger tables in this article. Kos. I to 

 VI, XI, and XII are, for convenience, placed in the appendix herewith ; 

 the rest are embodied in the text of the article. 



Table I. — Analyses of fish (protein estimated by multiplying nitrogen 

 by 6.25). In this table the specimens of fish are arranged in the order in 

 which the analyses were made. Each bears the laboratory number by 

 which it is referred to in the other tables and in the text. The " protein " 

 is estimated by multiplying the nitrogen by 6.25. The figures for both 

 " water-free substance " and "fresh substance " or flesh are given. For 

 reasons given in the text, under " Methods of analysis" and " Nitrogen- 

 factor of protein," I do not regard this as the most correct way of comput- 

 ing the analyses of materials which, like the flesh of fish, contain little of 

 uon-nitrogenous compounds other than fats and mineral matters, and 

 have made no further use of the results thus obtained. In deference, 

 however, to the very common usage of estimating "albuminoids" or 

 " protein " by multiplying the nitrogen by 6.25 and stating results of 

 analyses on this basis, I have given the results of all the analyses of the 

 flesh of fish in this way in Table I. 



Table II. — Analyses of fish (calculated on water-free substance, pro- 

 tein by difference). In this table the protein is estimated by subtract- 

 ing the sum of ether extract and ash from 100. 



The water-free substance consists essentially of nitrogenous com- 

 pounds, insoluble or nearly insoluble in dry ether; fats, soluble in 

 ether; and mineral matters, for the most part insoluble in ether and in- 

 cluded in the ash. The determinations of ether extract were made 

 in the nearly dried substance by use of purified and dried ether, and 

 represent very nearly the actual quantities of fats. The figures for ash, 

 though representing " crude ash," are a very nearly accurate measure 

 of the actual amounts of mineral matters. I believe it correct to as- 

 sume that the flesh of fish contains ordinarily but very little of non- 

 nitrogenous compounds, other than fats and mineral compounds, though 

 a more thorough study of the carbohydrates and complex nitrogenous 

 and phosphorized fats is much needed. Accordingly it seems to me 

 that in these analyses the most accurate measure of the nitrogenous 

 compounds is to be found by subtracting the sum of the ether extract 

 and ash from the whole. I have, therefore, in Table II, estimated the 

 percentages of protein by subtracting the sum of ether extract and ash 

 from 100. 



[35] 467 



