SUNIER: Marine fish-ponds of Batavia. 251 
SECOND EXPERIMENT. 
Consecutive number of Number of pulsa- 
the heart-beat synchron- Number of tions per minute. 
Moment of Time | izing with the moment pulsations in (In the perfectly 
of time marked in 10 seconds. undisturbed 
the first column. | embryo 140 — 143.) 
QuSeconds 7 and ho wih ende | 
0 0 
10 Seconds 0 
1 6 
20 Seconds 1 
3 18 
30 Seconds 4 
9 54 
40 Seconds 13 
10 60 
50 Seconds 23 
14 84 
60 Seconds 37 
14 84 
70 Seconds al 
18 108 
80 Seconds 69 
21 126 
90 Seconds 00 
24 144 
100 Seconds 114 | 
On other kepala timah eggs the influence of disturbances proved to 
be less than on the first egg on which I made the above observations. 
Fig. 29. The eggs of fig. 23—28 
a little more than 7 times 24 
hours after fertilization, X 1S. 
LIL, SI 
Fig. 30. The eggs of fig. 23—29 
a little more than 8 times 24 hours 
after fertilization. X 20. 
Thus an experiment on an artificially fertilized kepala timah ege, which, 
counted from the moment of fertilization was 8 times 24 hours old, and in 
which when perfectly at rest I counted 144 pulsations to the minute, yielded 
the following result: 
