866 REPORT OF COMMISSIONER OF FISH AND FISHER: . 
about it here. Perhaps, indeed, the most that can be said is 
there are people with whom such substances do not always agree, .yet 
oysters belong to the more easily digestible class of foods. 
FOOD VALUE OF FISH. 
The ingredients of the flesh of fish are essentially the same in kind as 
those of the flesh of domestic animals used for food, such as beef and 
mutton. The chief difference is that the flesh of fish contains relatively 
less fat and more water than ordinary meats. Or, to put it more spe- 
cifically, the flesh of fish contains in general about the same proportion 
of protein, less fat, more water, and hence on the whble less nutritive 
material, pound for pound, than that of domestic animals used for food. 
Thus we have in the flesh of flounder only 16 per cent., arid in that of 
cod 18 per cent., of nutrients, while ordinary lean beef has from 25 to 
to 33 per cent., and the fatter meats considerably more. The fatter 
kinds of fish, however, as herring, mackerel, salmon, shad, and whitefish 
approach nearer to medium beef. Dried and salted fish also contain 
good proportions of nutrients, the specimens of ordinary salt codfish 
having 28 per cent., salt mackerel 47, and desiccated cod, a material as 
yet less known commercially, 82 per cent, of nutrients. The edible 
portion of shellfish is poor in nutrients, oysters varying from 9 to 19, 
and lobsters averaging 18 per cent. 
Fish as found in the markets generally contain more refuse, bone, 
skin, etc., than meats, as is illustrated in Tables Vi and viii. With 
the larger proportions of both refuse and water the proportions of 
nutrients, though variable, are usually much less than in meats. Thus 
a sample of flounder contained 67 per cent, of refuse, 28 of water, and 
only 5 per cent, of nutritive substance, while the salmon averaged 23, 
the salt cod 22, and the salt mackerel 36 per cent, of nutrients. The 
nutrients in meats ranged from 30 per cent, in beef to 46 in mutton and 
87J in very fat pork (bacon). The canned fish compare very favorably 
with the meats. It is worth noting that the nutrients in dressed fresh 
codfish, in edible portion of oysters, and in milk were nearly the same in 
amount, about 12£ per cent., though differing in kind and proportions. 
Vegetable foods have generally less water and more nutrients than 
animal foods. Ordinary flour, meal, etc., contain from 85 to 90 per 
cent, or more of nutritive material. But the nutritive value is not pro- 
portional to the quantity of nutrients, because the vegetable foods con- 
sist mostly of carbohydrates, starch, sugar, cellulose, etc., of inferior 
nutritive effect, and because their protein is less digestible than that of 
animal foods. Potatoes especially contain a large amount of water and 
extremely little protein or fats, 
