444 REPORT OF COMMISSIONER OF FISH AND FISHERIES. [18] _ 
fully measured on the split fish, by laying a thick sheet of paper over it — 
and cutting this sheet so as to fit exactly. The skin, from a cross-cut 
ot the body, measuring 8 or 9 centimeters in breadth, was prepared and 
weighed; and, by comparing the weight of a piece of paper of equal size 
with that of the large piece of paper mentioned before, the approximate 
weight of the entire skin was determined. 
Grams 
Mhe weight of the fish was. -as. 322k ce see 89. 30 
Subtract the above mentioned portions (the blood which had run 
out being estimated at 47 grams, and the mature ovarium at 
BOW STAMS) 2s se aiid eee ows ae eee ee 25. 90 
And there remains forthe muscle.....4 . oo 2eee eee - 63. 40 
We will now endeavor to find whether the probable loss of substance 
which, according to our average figures, will be sustained by the muscle, 
is sufficient for building up the ovarium. The decrease of weight of the 
entire animal, with the exception of the loss of some intestinal fat and 
part of the liver, will almost exclusively be a decrease of muscle, as the 
skin does not show any visible layer of fat, and, as is well known, the 
head and fin muscles hardly decrease at all. 
Table VI shows us a possible way of calculating the probable de- 
crease in weight, at any rate till the 12th of October. From the 7th of 
August to the 12th of October its weight would probably decrease from 
105.78 to 100 grams. The spawning season, however, does not com- 
mence till the middle of November, and the fish which we had before 
fore us (with an ovarium weighing 279.5 grams=3.13 per cent. of the 
entire weight of the body) would be classed among his cotempo- 
raries which had been examined (see Table I), among the less advanced 
as to its sexual maturity, and would probably not have spawned till 
the end of November or the beginning of December. We may there- 
fore, further calculate the decrease of weight on the basis of the last 
period till the 11th of November = 30 days, all the more as just as many 
fish after the 12th October, as before that date, have been used for eal- 
culating the final weight. Going on this supposition, 2.77 per cent. will 
yet have to be subtracted from 100, and the final weight sought will be 
97.23 91.92 
8 T0578 1007 ee 
able loss of weight 8.08 per cent. of 8,930, would be 722 grams; the final 
weight at the spawning-period would be 8,9380—722 = 8,208 grams. The 
probable weight of the ovarium will be 23 per cent. of this final weight 
(Group V, Table 1), 1,888 grams. 
to the weight of the 7th of August (8,930) 
