NATURAL RHYTHM, 153 
of the segments than in that of others. I therefore 
observed the segments over five-minute intervals, 
instead of one-minute intervals as on the previous 
day. 
The following is a sample of several observa- 
tions, all yielding the same general result. 
Segment }. Segment 4. Segment 3 A. Segment 3 B. 
Number of | Seconds of Continued per- | Rhythm toler- 
per conec) apie sistently to | ably perfect 
12 120 ‘ contract with | at 78 in the 5 
3 10 No motion | a nearly per- | minutes; but 
5 20 during the | fectrhythmof | this was occa- 
44 130 hourofob- | 78 in the 5| sionally in- 
2 20 servation. minutes dur- | terrupted by 
ing the hour | long pauses of 
é of observa- 4 or 5 minutes’ 
73 5 min. | tion. duration. 
Continuous Interrupted 
Average rate : rhythm atthe | rhythm at the 
14+ per minute. Reet aor 153 per | rate of 152 
minute. 
per minute. 
I now transferred all the segments to fresh sea- 
water, with the following results :— 
Rhythm during first quarter of an hour immediately after trans- 
ference, in five-minute intervals. 
Time. 
First 5 minutes. 
Second 5 minutes. 
Third 5 minutes. 
Segment i. 
100 (regular). 
139 (irregular).} 0 
0 0 
Segment 1. 
Segment 3 A. 
Segment 3 B. 
83 (regular). | 20 (irregular). 
68 7 
39 (irregular). | 70 oe 
5 (regular). 
6 
Rhythm two hours after transference (five-minute intervals). 
Segment 3. 
82 (regular). 
Segment 1. 
77 (regular). 
Segment 4 A. 
70 (regular). 
Segment 3 B. 
62 (regular). 
