494 
BULLETIN OF THE BUREAU OF FISHERIES 
Table 4. — Oxygen consumption of normal oysters 
Experiment 
Date 
Oyster 
Time 
pH 
Os tension, 
c. c. per 
liter, 0 0 C 
760 mm. 
O2 consumption, 
c. c. per hour per 
10 grams dry weight 
Remarks 
Single 
determi- 
nation 
Average 
8 
2. 30 
4. 66 
15. 04 
2. 45 
4. 60 
3. 00 
4. 22 
13. 92 
3. 15 
4.04 
14. 32 
3. 30 
3. 75 
14. 20 
3. 45 
3. 40 
17. 70 
9 
July 29 
34-39 incl 
11. 10 
8. 30 
4. 33 
10. 29 
Do. 
11. 35 
8.20 
3.91 
10. 65 
12. 10 
8.11 
3. 44 
10. 20 
12. 40 
8.02 
3.31 
10. 50 
1. 10 
7.98 
2. 92 
9. 81 
10 
12. 20 
7.9 
3. 98 
6. 45 
Do. 
12.50 
3. 08 
6. 28 
1. 20 
7.8 
2. 72 
6. 28 
1.50 
7.7 
2.24 
5. 93 
2.20 
7.6 
1.94 
6.84 
2.50 
7.5 
1.69 
5. 45 
3.20 
7.5 
1.43 
7.68 
11 
10. 45 
7. 9 
3. 60 
8. 70 
Do. 
11. 15 
7.8 
3. 06 
7.96 
11. 45 
2. 46 
10. 50 
r 
12. 15 
7.6 
2.11 
8.66 
12 
10. 45 
4. 76 
9. 16 
Do. 
11. 00 
4. 49 
7. 86 
11.30 
4. 02 
9. 20 
12.00 
3. 62 
8.95 
12.30 
3. 05 
9.04 
1.00 
2.72 
10.01 
2.00 
2.07 
9.81 
13 
Aug. 9_ 
9. 50 
3. 495 
10. 99 
Do. 
10. 20 
2. 865 
14. 50 
11.20 
2.06 
10. 52 
11. 50 
1.713 
9. 60 
12.50 
1. 37 
9. 35 
74 
Aug. 17 
74 
11. 00 
4. 24 
8. 97 
Open chamber method. 
11.30 
3.93 
9.80 
12. 00 
3. 53 
11.46 
12.30 
3.24 
7. 65 
75 
75 
9. 15 
8.0 
4. 60 
9. 86 
Do. 
9.45 
8.0 
4. 26 
10. 49 
10. 15 
7.9 
3.89 
9. 94 
10. 45 
7.7 
3. 74 
8. 15 
76 
76 _ 
1. 35 
4. 07 
7. 73 
Do. 
2.05 
3.87 
5.71 
2. 35 
8. 75 
3. 05 
3. 45 
8.75 
77.. 
Aug. 31 
77_ — 
11. 30 
8.0 
9. 78 
Do. 
12.00 
7.9 
10. 08 
12. 30 
7.9 
9.72 
1.00 
7.9 
9. 56 
81 
Sept. 12 
81 .. 
9. 30 
10.78 
Do. 
10. 00 
11. 58 
10. 30 
10. 80 
11. 00 
9. 97 
In experiments 74, 75, and 81, determinations were made on single oysters the 
shells of which were connected to a kymograph. An analysis of the kymograph 
tracings disclosed the fact that there existed a considerable difference in the muscular 
activity of these oysters. For instance oyster No. 74 opened almost immediately 
and remained wide open with scarcely any contractions of the muscle. (Fig. 3 C.) 
Oyster 81 remained tightly closed for a little over 1 hour, then when it did open, the 
muscle went through a series of vigorous contractions (fig. 3 A) which lasted as long 
as the experiment was continued. Oyster 75 (fig. 3 B) in respect to the muscular 
