EK. W. BERGER ON THE CUBOMEDUSA. 39 
CASSIOPEIA. 
[The remaining experiments were all performed in 1897, at Port 
Antonio. | 
49. Removal of the sixteen marginal bodies caused paralysis for 
a time; then recovery followed. 
Contraction was limited to the subumbrella. 
A portion of the swbumbrella not from the margin can contract 
by itself as well as a portion of the margin with the marginal bodies 
(lithocysts). 
In the margin cut off as a strip with only one marginal body 
attached at one end, contractions sometimes started from the opposite 
end. 
AURELIA. 
50. Size, seventeen or eighteen millimeters. Pulsations, thirty-two. 
Lithocysts, nine. The operation consisted in the removal of the 
concretions with as little injury to the pigmented parts of the 
marginal bodies as possible. One whole marginal body, however, was 
removed in the operation. Soon after the operation the pulsations 
were 28, 26, 20, 20, per minute. 
Another one; size fifteen millimeters. Pulsations were forty per 
minute. The operation consisted in the removal of the concretions 
and pigmented parts of the marginal bodies with as little injury to 
the adjoining parts as possible. After the operation it seemed as if 
the intervals between the pulsations were irregular,—not a series at 
regular intervals. An hour or so after the operation the pulsations 
were very intermittent. During the afternoon it was not seen to 
pulsate except when it was stirred up, when six or seven vigorous 
pulsations followed. These, however, were rather aimless. 
51. One sensory club (marginal body) was cut out, including its 
basal part also. In one or two other cases more or less injury was 
done to adjoining parts also. Pulsations ceased upon the removal of 
the last club, but upon placing it in an aquarium and allowing it to 
come to rest for two or three minutes, pulsations were now and then 
seen. In the evening, this one and another did not pulsate except 
when stirred, when they pulsated with good progress. 
52. A circular cut, about two inches in diameter, was made 
through the epithelium of the subumbrella around the base of the 
