242 Papers from the Department of Marine Biology. 
Two methods of desirable experimentation presented themselves. 
One was to in some way reverse the natural current in order that it 
might pass in a reversed direction through the cells for some long pe- 
riod. This was found impracticable in the time at my disposal. The 
electric organs could not be reversed by an operation, owing to their 
large size and vital connections; still less could the brain-parts be dis- 
placed or operated upon. It was attempted to disconnect the electric 
organ from the brain by an incision which might cut the electric nerves 
and then to substitute an artificial current through the brain of 
strength equal to the natural one for considerable periods, but the 
fish all died, not being able to survive the operation. It is hoped in 
the future to be able to do this with an improved technique. 
The second method was to excise portions of the electric lobes and 
to subject them while fresh and living to electrical currents of various 
kinds. This was done in 6 cases, Nos. 3, 4, 5, 6, 7, and 10. These 
results will now be considered. 
The first experiments consisted in passing direct currents, of a 
strength approximately equal to that of the fish’s own current as found 
passing through the brain, through the cells in question in a direction 
at right angles to the natural current and also in a reverse direction. 
It was not easy to estimate the strength of this current in the fish at 
the point where it passed through the brain, but a rough estimate was 
made and some small batteries were arranged so as to give an approxi- 
mately equal current. This current was passed (torpedo No. 7) through 
a cylindrical bit of the electric tissue which was cut out of the electric 
lobes so as to be 4 mm. in diameter and 1 cm. long. This was placed 
in a glass tube and platinum electrodes were used to lead in the current. 
The tissue was cut so that its long axis was anterior-posterior or at 
right angles to the dorso-ventral line through which the natural current 
passes. 
This experimental current was allowed to pass through the tissue 
for half an hour. Then the tissue was fixed and cut, but the sections 
agreed exactly with the control, so that the current made no change in 
the structure. Other currents of varying strength that approximated 
the natural current were used, some of them clearly as strong or stronger 
than the natural current. No. 6 was arranged so that the experimental 
current was in a direction reversed to the natural current. The time 
in this case was 1 hour, easily past the time during which the tissue 
lived. In both these cases no positive result was attained, and it 
seems to show that the plasmosome is not moved by these currents. 
Whether it would be moved by such currents if they were applied to it 
while it still lived, for weeks or months, can not be said. Currents of 
this sort which do not. kill the tissue have been applied to plant cells 
by McClendon (25), also by Pentanalli (29), and to animal cells by 
Conklin (9) and Lillie (23). 
