PRIMARY INHIBITION OF CILIARY MOVEMENT 421 
from one of the short walls of the basin a swimming plate (no. 1) 
is observed striking automatically, with at least five strokes 
a second when there is no current. ‘The nearest electrode is made 
the cathode. A current of 7 milliamperes (approximately = 
19.4 m.amp./em.2) is closed through the chamber (1 h. 41 m.). 
Swimming plate no. 1 continues, as far as the eye can judge, to 
strike with unaltered rapidity. In addition, an adjacent swim- 
ming plate (no. 2), which had formerly been still, also begins to 
vibrate. The current is broken. 
1h. 46m. No ciliary element within the field of vision 
vibrates when there is no current. After a current of the same 
strength as at 1 hr. 41 m. has been kept closed for 12 seconds 
another swimming plate (no. 3), which was previously motion- 
less, begins to strike. The circuit is opened. 
1h. 50m. Conditions at start: Without any current neither 
no. 1, 2, nor 3 vibrate. A current of the same strength is closed. 
After 10 seconds no. 3, ‘and after 3 more seconds, no. 2, begins to 
vibrate. No.1 remains motionless. ‘The current is now broken. 
1h. 54m. Conditions at start: no. 2 and 3 are vibrating, no. 
1 is still. A current of 6.5 m.amp. is closed (density approxi- 
mately = 18.1 m.amp./em.?). The two first-mentioned swim- 
ming plates continue to move with increasing intensity, but stop 
immediately when the current is shut off. No. 1 was still the 
whole time. The circuit is broken. 
2h. 29m. Another swimming plate at a distance of only 4 
mm. from one of the strips of rattan vibrates rapidly without 
any current. ‘The nearest electrode was made the cathode. A 
current of 6.5 m.amp. (approximately = 18.1 m.amp./em.’) pro- 
duces a violent increase in the frequency of vibration, which 
continues until, after 10 seconds, the current is shut off. 
2h. 34m. Another swimming plate at a distance of 4 mm. 
from the cathodic strip strikes spontaneously without any current. 
A current of 1.5 m.amp. (approximately 4.2 m.amp./cem.’) is 
closed. During the 10 seconds the current is kept closed the 
frequency of the ciliary motion in the plate in question is only 
accelerated. 
