442 On the Composition of Oxen, Sheep, and Pigs. 
laboratories of tlic food, with their contents, the further elaborating 
organs (if we may so call them) with their fluids, appear to be 
much more equal in their proportion in the three cases. 
This point is approximately illustrated in the fact that, taking 
together the recorded percentages of " heart and aorta," " lungs 
and windpipe," " liver," " gall-bladder and contents," " pancreas," 
" milt or spleen," and the " blood," the sum is for the oxen about 
7 per cent, for the sheep about 7^ per cent., and for the pigs 
about 63 per cent. If from this list we exclude the blood, which 
was more than one-third of a pei-cent. lower in the pig than in 
the other animals, the sums of the percentages of the otlier parts 
enumer.ated, would agree still more closely for the three descrip- 
tions of animal. 
Lastly, in regard to the distinctions between the different de- 
scriptions of animal : of the masses of internal " loose fat," with 
its connecting membrane, the oxen yielded on the average about 
4^ per cent., the sheep about 7J per cent, and the pig little more 
than 1^ per cent. The pig, therefore, with its much less propor- 
tion of alimentary organs, has also a much less proportion of the fat 
which surrounds them. With regard to the much larger amount 
of this sort of fat indicated in the sheep than in the oxen, it may 
be remarked that a considerable proportion of the sheep which 
contribute to these recorded averages were, compared with the 
oxen, in more than a corresponding degree of maturity and fatness. 
A rapid survey may next be taken of the relative development 
of the several organs and parts, as the animal progresses in ma- 
turity and fatness. 
An examination of the Tables (IV.-IX.) shows that the internal 
organs and other " offal " parts pretty generally increase in actual 
weiglit as the animal passes from the store or lean, to the fat or 
to the very fat, condition ; but that, excluding the loose fat — 
which increases not only in actual weight but proportionally — 
their percentacje proportion in the whole body as invariably dimi- 
nishes as the animal matures and fattens. 
The carcasses, on the other hand, invariably increase both in 
actual and in percentage amount, as the animals mature. 
The above remarks apply generally to oxen, sheep, and pigs ; 
but the data relating to the sheep comprise the most complete 
gradationary series for their illustration. 
Thus, the average actual weights per head of the collective 
stomachs and intestines, and their contents, increased from about 
13|lbs. in 5 store or /mw sheep, to about 15J lbs. in IQOfat sheep, 
and to about IGi lbs. among 45 very fat ones. Again, the heart 
and aorta, the lungs and windpipe, the liver, the gall-bladder and 
contents, the pancreas (sweetbread), the milt or spleen, and the 
blood, 
