148 
BULLETIN OF THE BUREAU OF FISHERIES 
in water. He found that the effect disappears at about 1 part per thousand, and that 
no water is pumped at about 8 parts per thousand. The latent period curves become 
approximately straight at these two limits, suggesting that the effect of the liquor 
noted by Galtsoff is produced directly through sensory or nervous channels. 
DISCUSSION OF RESULTS 
It is unfortunately impossible to present in a single graph all of the results which 
have been described in the foregoing, account. In the first place the results fall into 
two groups, depending upon whether the specimens died during the period for which 
the tests were continued, or whether at this time they were still living but reacting in 
some other manner to the liquor. Large individual variations in susceptibility make 
it difficult to express the results mathematically. 
In Table 2 the essential points of the results are given to show the difference between 
the activity of the experimental oysters and that of the controls. The records of the 
two control specimens of a series are averaged to serve as a basis for comparison with 
the treated oysters. The percentage of reduction, from the normal or control records, 
in the number of hours per day that treated specimens remain open is given for each 
oyster. In these values there is a great variation. This is due, in the first place, to 
the fact that all experiments were not continued equally long, and also to the marked 
individual difference in behavior of two specimens in the same solution. In the 
descriptions of the individual experiments it was pointed out that, when treated with 
a certain concentration of liquor, one specimen might remain open as much, or almost 
so, as the controls, and die within a few days, while the other specimen might protect 
itself by remaining closed a large proportion of the time, with the result that it would 
live longer. Why this variation should be so great is not clear. 
Table 2. — Summary of data on the effect of sulphite liquor on the Olympia oyster, showing death time 
and percentage of difference in time open between control and, experimental specimens 
[In certain cases, designated by (— ), the control? were open slightly less than the experimental oysters (see text description)] 
Experiment number 
•Concen- 
tration 
parts per 
thousand 
Specimen 
number 
Death 
time in 
days 
Hours per 
day open 
Controls 
average 
hours per 
day open, 
2 speci- 
mens 
Differ- 
ence (in 
hours per 
day open) 
between 
experi- 
mental 
and con- 
trol speci- 
mens 
Per cent 
difference 
6.0 
3 
2 
14,3 
21. 03 
6.73 
32.0 
10.0 
{ 2 
14 
7.7 
2.4 
10.4 
22. 5 
} 22.85 
{ 2^ 45 
66.3 
5.0 
{ 6 
15 
13 
} 22. 85 
1 12! 45 
\ . 35 
54! 5 
5.0 
{ 6 
20 
i. 41 
} 23. 08 
r 18! 67 
80! 4 
10.0 
{ 2 
6 
5.55 
} 23. 08 
{ 1 9 48 
75! 9 
2.4 
{ 2 
29 
14! 25 
} 19.28 
{ 3" 14 
26! 1 
3.2 
f 5 
12 
19! 6 
} 19.28 
{ li' 98 
—l! 5 
1.3 
f 1 
19 
17.' 2 
} 21.0 
{ 19 3 
is! 1 
2.0 
f 5 
24 
12! 93 
} 21.0 
{ n'-? 7 
43.' 2 
.67 
{ 2 
28 
16! 21 
14. 49 
23. 66 
fi 74 
} 22. 34 
/ 6! 13 
l 7.85 
/ -1.32 
l 15. 60 
/ 12. 15 
27.’ 4 
35.1 
-5.9 
1.0 
f 5 
i 6 
15 
} 22. 34 
3.8 
/ 1 
ll! 46 
51." 4 
19.7 
1. 3 
13 
i 2 
18.96 
23.3 
| 23. 61 
l 4.65 
{ l'08 
1.8 
/ 5 
} 23. 61 
19 
22. 53 
15.82 
f 1 
} 17. 82 
/ 2! 00 
l -9.71 
{ _ 4 g2 
ll! 2 
54.4 
27! 1 
61.1 
q 
.7 
2 
8.11 
19.21 
.44 
f 5 
} 17. 82 
A 
13.0 
7. 06 
r i 
} 18. 15 
f ll! 09 
1 11. 39 
/ 9.64 
1 8.66 
. 5 
6.76 
8.51 
.83 
f 5 
[ 18. 15 
53! 1 
47.7 
2 
l 6 
9. 49 
