6 BULLETIN 740, U. S. DEPARTMENT *0F AGRICULTURE. 
no appreciable amount takes placfe while the oysters are stored in 
the refrigerating room of the oysterhouse for a short time. It is 
interesting to note that the figure for the larger oysters, selects and 
counts, is uniformly smaller than that for the standards of the same 
stock. 
From the results obtained in this series, there appears to be no 
relation between the amino-acid nitrogen and the ammoniacal 
nitrogen present. In general, the figures for ammoniacal nitrogen 
change in the same way as do those for aminoacid nitrogen; but the 
former are so inconsistent, even in duplicates run on the same sample, 
that the whole table is practically meaningless in this connection. 
Similar determinations were run in all the following series of experi¬ 
ments, but as they are in all cases as conflicting as those in Tables 1 
and 2, they have been omitted from all subsequent tables. 
SERIES II. 
In order to prove that the amount of amino-acid nitrogen and 
ammonia present would not indicate decomposition in oysters if the 
water over them was changed occasionally, the following series of 
experiments was run. 
A 5-gallon can of oysters was divided into two lots, and the oysters 
in each were covered with water. One lot was stored at room temper¬ 
ature, the other in a small ice box at a temperature of about 45° F., 
and the water over each lot was changed every day. Determina¬ 
tions were run upon each lot every day for one week. A summary 
of results obtained is given in Table 2. 
Table 2. — Amino-acid and ammoniacal nitrogen as index of decomposition. 
1,1 ■ 
Date of analysis. 
Amino-acid nitrogen 
in portion stored at— 
Ammoniacal nitrogen 
in portion stored at— 
Room temp. 
45° F. 
Room temp. 
45° F. 
1914. 
Oct. 5. 
Per cent. 
0.1290 
.1280 
.1244 
.1075 
.1250 
.1250 
.1215 
Per cent. 
0.1290 
. 1280 
.1272 
.1120 
.0687 
.0676 
.0638 
Per cent. 
0.00123, 
.00116 
.00329 
.00165 
.00392 
.00185 
.00473 
Per cent. 
0.00123 
.00116 
.00259 
Oct. 6.,. 
Oct. 8. 
Oct. 9. 
.000105 
.000098 
.000840 
Oct. 10. 
At the end of this time the oysters soaking at room temperature 
were badly decomposed. In spite of this condition, the amino-acid 
nitrogen content decreased, and the figure for ammoniacal nitrogen, 
though larger than in the same oysters at the beginning of the experi¬ 
ment, was smaller than that found in several samples of fresh oysters. 
The oysters stored in the refrigerator kept much better than those 
stored at room temperature, though they also were slightly decom- 
