CHEMICAL COMPOSITION OF FOOD-FISHES. 833 
several experiments with more than one person ; with others, as eggs, 
corn meal, rice, pease, and potatoes, only a single trial has been made. 
Doubtless extended series of tests would give averages differing 
■ more or less from these figures ; some food materials may be more 
completely digested when taken in small quantities with others in the 
ordinary way than when so much is eaten and without any other food; 
these and other sources of slight error make more extended experiments 
very desirable ; but enough has been done to show pretty clearly that — 
1. The protein of our ordinary meats and fish is very readily and com- 
pletely digestible. 
i 2. The protein of vegetable foods is much less digestible than that of 
animal foods. Of that of potatoes and beets, for instance, a third or 
more may escape digestion and thus be useless for nourishment. 
3. Much of the fat of animal food may at times fail of digestion. 
4. The carbohydrates, other than fiber, which make up the larger 
part of vegetable foods, are very digestible. 
5. Animal foods have in general the advantage of vegetable foods 
in containing more protein; and their protein is more digestible. 
6. The comparative digestibility of fish and meats and of the differ- 
ent kinds of fish is not well enough decided by experiment to warrant 
1 as definite conclusions as are desirable. The leaner meats are proba- 
bly more easily digested than those with more fat, and the leaner kinds 
of fish, such as cod, haddock, perch, pike, bluefish, sole, flounder, etc., 
are more easily and completely digested than the fatter kinds, as salmon, 
shad, and fat mackerel ; and fish, which is, in general, less fat than meat, 
is on the average more digestible. 
7. 'People differ in respect to the action of foods in the digestive appa- 
ratus, and fish, like other food materials, are subject to these influences 
of personal peculiarity. 
3. TABLES OF ANALYSES OF FISHES, MOLLUSKS, ETC. 
Table Yl. (Chart A.) — Recapitulation of analyses of American and European food- 
fishes. Nutrients and water in flesh {edible portion). 
[Arranged in order from those with largest to those with smallest percentages of total nutrients.] 
Kinds of fish. 
(A, American]; E, European.) 
In flesh. 
Protein. 
Fats. 
Ash. 
Total. 
Water. 
Energy in 
1 pound of 
each ma- 
terial. 
'California salmon, A. : 
Per ct. 
Per ct. 
Per ct. 
Per ct. 
Per ct. 
Calories, 
Maximum 
16. 96 
19. 25 
1.11 
37.32 
62. 68 
1, 125 
Minimum 
17. 96 
16. 50 
1. 01 
35. 47 
64. 53 
1. 030 
Average 
17. 46 
17. 87 
1 1.06 
36. 39 
63. 61 
1. 080 
Eel, A and E: 
Maximum 
13. 42 
32.88 
! 0.92 
47. 22 
52. 78 
1.635 
Minimum 
17.61 
7. 88 
1 1.11 
26.60 
73. 40 
660 
Average 
15. 82 
18. 74 
0. 93 
35.49 
64. 51 
1, 085 
Salmon, A and E : 
Maximum 
24.45 
13. 07 
1. 45 
38. 97 
61.03 
1. 005 
Minimum 
18. 17 
4.85 
1.28 
24. 30 
1 75. 70 
545 
Average 
20.77 
12. 09 
1.38 
34.24 
1 65. 76 
895 
Spanish mackerel, A 
20. 97 
9. 43 
1.50 
! 31.90 
i 68. 10 
.790 
H. Mis. 274 53 
