SECTION OF COVERED-EYED MEDUSA. 101 
of a drop of spirit, the resulting waves of contraction 
are almost sure to pass across the isthmus, even 
though this has been exhausted in the manner just 
described. 
Gunglia appearing to assert their Influence at w 
Distance from their own Seat. 
Another fact, which I have several times noticed 
during my sections of Aurelia, also deserves to be 
recorded. I have observed it under several modes 
of section, but it will be only necessary to describe 
one particular case. 
In the Aurelia of a portion of which the accom- 
panying woodcut (p. 102) is a representation, seven 
of the lithocysts were removed, while the remaining 
one was almost entirely isolated from the general 
contractile tissue by the incisions aa, bb, cc. The 
lithocyst continued to animate the tissue-area vxea, 
and through the connecting passage y the con- 
traction-waves spread over the remainder of the 
sub-umbrella tissue zzzz. So far, of course, the facts 
were normal; but very frequently it was observed 
that the contraction-waves did not start from the 
lithocyst, or from the area axax, but from the point 
o in the area zz. After this origination of the 
contraction-waves from the point o had been ob- 
served a great number of times, I removed the 
lithocyst. The effect was not only to prevent the 
further origination of contraction-waves in the area 
xxax, but also to prevent their further origination 
from the point o, the entire umbrella thus becom- 
