REPORT OF COMMISSIONER OF FISH AND FISHERIES. 
ion of each specimen as received for analysis. Where the . • 
consisted simply of the edible portion, as in the case of the “ solids 77 of 
oysters, canned oysters, etc., the percentage of total edible portion is, of 
course, 100. 
I have already stated that some of the conclusions as to the values 
of fats, which are ordinarily drawn from the chemical composition of 
meats and fish, are not ventured upon here because the precise nature 
of the nutritive ingredients of oysters and other shellfish is not defi- 
nitely understood. 
Perhaps further experimental study will show that what we call the 
protein of the oyster is very nearly the same as that of meat or milk ; 
that what we reckon as carbohydrates of the shellfish have about the 
same nutritive value as the carbohydrates of other foods — milk, sugar, 
and starch, for instance. Meanwhile, what is known implies that the dif- 
ferences are probably not very great, though they may be considerable. 
The composition of the liquid portion demands a few words of expla- 
nation. The amount of nutriment is very small indeed, the principal 
constituents being water and salts of sea water. How much food value 
these minute quantities of nutriment have it is impossible to say. Per- 
haps a given weight of what is called protein in the liquids of oysters 
may be not far inferior to the same quantity in the flesh, but this is a 
matter of doubt. 
Taking all in all, the variations in composition of oysters are very 
wide. The same would very likely be found to be the case with clams 
and other shellfish if a large enough number of analyses were made to 
show the range of variation, but probably the averages of the analyses 
here given represent pretty nearly the average composition of the shell- 
fish as they are ordinarily found in the water and in the markets. 
Most of the specimens of oysters and other shellfish here reported upon 
were received without statement as to whether they had been u floated” 
or not, but we suppose that, except when otherwise stated, they had 
usually been floated and the specimens were such as are ordinarily sold. _ 
The effect of floating on the composition is described in another place 
in this report. Briefly stated, floating increases the proportions of water 
and diminishes the proportions of nutritive ingredients, and especially 
those of mineral salts. Floated oysters will therefore have on the aver- 
age more water and less nutritive material than those not floated. 
The same is true of clams, mussels, etc. 
It is then safe to say that while the variation in the composition of 
oysters, clams, and the like are considerable, just as they are in different 
kinds of meat, such as beef, mutton, and pork, yet it is probable that 
the proportions which are expressed in the figures of Table I, and 
graphically set forth in the colored diagram, make a reasonably fair 
exhibit of the average composition of these food materials in the con" 
dition in which we ordinarily buy them, and hence represent pretty 
nearly their relative nutritive values. While we must wait for further 
