ARTIFICIAL RHYTHM. 187 
Coming, then, to experimental tests, we have 
already seen that in the deganglionated swimming 
organ of Aurelia aurita, rhythmic response is yielded 
to constant faradaic stimulation of low intensity. 
The next question, therefore, which presents itself 
in relation to our subject is as to whether other 
modes of constant stimulation elicit a similar re- 
sponse. Now, in a general way, I may say that 
such is the case, although I have chosen faradaic 
stimulation for special mention, because, in the first 
place, its effect in producing rhythmic action is the 
most certain and precise; and, in the next place, 
the effects of administering instantaneous shocks 
at given intervals admit of being compared with 
the effects of constant faradaic stimulation better 
than with any other kind of constant stimulation. 
Nevertheless, as just stated, other modes of con- 
stant stimulation certainly have a more or less 
marked effect in producing rhythmic response. The 
constant current, during the whole time of its 
passage, frequently has this effect in the case of 
the paralyzed nectocalyx of Sarsia ; and dilute spirit, 
or other irritant, when dropped on the paralyzed 
swimming organ of Aurelia aurita, often gives rise 
to a whole series of rhythmical pulsations, the sys- 
toles and diastoles following one another at about 
the same rate as is observable in the normal swim- 
ming motions of the unmutilated animal. 
From this it will be seen that, both in the case 
of mechanical and of chemical stimulation, the same 
tendency to the production of rhythmic response 
on the part of the paralyzed tissues of Aurelia may 
