444 LIVING TORPEDOS IN BERLIN. 



manifested a good strong organ-current. In another Torpedo 

 26 cm. in length which had been even longer in captivity, and in 

 which I did not experiment on the organ-current of the whole fish, 

 I found the bundles of columns to act very regularly, and in some 

 instances with considerable force. 



The diminution of force of the organ-current in badly nourished 

 animals would explain the fact that I found none in strips of 

 the Malapterurus organ even with the nerve-multiplier. As 

 regards what Eckhard considered his negative results, it will 

 be seen on closer examination that they are not altogether in- 

 consistent with ours. Of his experiments on the whole fish, of 

 which to prevent voluntary discharges and movements the brain 

 and spinal cord were destroyed, Eckhard remarks, ' The needle 

 was seldom completely at rest but the deflections were always very 

 small, and frequently at all events corresponded in direction to 

 such a current as would be induced in the organ by the excitation 

 of its nerves. There was, however, no permanent deflection.' Of 

 experiments on bits of an organ led off from the ventral and 

 dorsal surfaces he says, ' The deflections had often the same 

 direction as above noted ; they were not, however, to be com- 

 pared with those resulting from much smaller portions of muscle 

 of the same animal/ The organs and parts of organs gave 

 shocks on excitation of their electrical nerves l . What this 

 amounts to is simply that Eckhard expected stronger currents than 

 those he actually observed, a circumstance which was due to the 

 defective sensibility of his galvanometric apparatus. The absence 

 of permanent deflections is explicable by the circumstance that 

 Eckhard still used platinum for leading-off. 



In the bundles of columns taken from the median part of the 

 organ, it sometimes happens that nerve branches protrude from the 

 middle of their length, as out of the tubes of a muscle. If a bit of 

 nerve is cut off from the preparation a shock follows which may 

 even drive the scale out of sight. Matteucci described a similar 

 effect, having observed twitchings in a nerve muscle preparation in 

 contact with bits of organ only as big as pin heads, when these were 

 mechanically excited 2 . I tried in vain, however, to excite the 

 bundles of columns with ammonia, although Sachs had succeeded in 

 doing so with portions of the organ of Gymnotus 3 . The reason is 

 clear, viz. that in bits of the Torpedo organ it would only be 



1 Beitrage zur Anat. und Physiol., vol. i. pp. 159-162. 



1 Untersuchungen, pp. 175, 176. Ibid. pp. 177, 178. 



