666 
ME. G. J. EOMANES ON THE LOCOMOTOE SYSTEM OF MEDUSA. 
Sarsia. 
Sarsia (another specimen). 
Number of 
pulsations. 
Seconds of 
rest. 
Number of 
pulsations. 
Seconds of 
rest. 
54 
90 
40 
60 
20 
15 
29 
90 
9 
92 
32 
132 
51 
40 
33 
92 
38 
60 
18 
59 
1 
43 
8 
63 
63 
45 
15 
35 
1 
14 
2 
85 
60 
15 
11 
63 
6 
50 
30 
33 
38 
50 
17 
81 
22 
32 
19 
67 
25 
12 
3 
65 
56 
55 
19 
36 
65 
20 
41 
123 
42 
15 
80 
23 
35 
40 
61 
150 
76 
43 
45 
145 
40 
120 
10 
97 
14 
35 
These observations may be taken as samples of others which it would be unnecessary 
to quote, as it will be seen from the above that there is no precise relation between the 
number of the pulsations and the duration of the pauses. Nevertheless, that there is 
a general relation may be seen from some cases in which unusually prolonged pauses 
occur. The following instance will serve to show this : — 
Sarsia (another specimen). 
of pulsations. 
Seconds of rest. 
38 
30 
22 
35 
49 
40 
30 
45 
46 
20 
2 
15 
24 
380 
112 
20 
45 
185 
894 
30 
6 
45 
4 
140 
2 
185 
30 
240 
200 
60 
In this case the relation between the long pause of 380 seconds and the subsequent 
prolonged swimming bout of 112 pulsations, is obvious. Also, as the latter was then 
followed by a short pause of 20 seconds and another comparatively short bout of 45 
pulsations, the refreshing influence of the previous 380 seconds of rest may be supposed 
to have been not quite neutralized by the exhausting effect of the foregoing 112 pulsa- 
