10 MUSEUMS. 



points in structure constantly arising for settlement, and the making 

 of preparations essential to the full understanding of the exhibited 

 specimens, have been impossible ; while others could be carried out only 

 imperfectly and with difficulty. 



The Electric Cat-Fish {Malapterurus electricus), which has been for 

 many years past a great desideratum among physiologists, having this 

 year been successfully imported, and thriven well, an opportunity was 

 afforded of granting to Professor Gotch, F.R.S., Waynflete Professor 

 of Physiology, Oxford, who at the time of their arrival was Professor of 

 Physiology in University College, Liverpool, the opportunity of 

 investigating the characters of the discharge of the electrical organ. 

 Professor Gotch, who while in Liverpool conducted his experiments, both 

 in the Museum and at University College, was with the permission of the 

 Committee supplied with several specimens at Oxford. In gratefully 

 acknowledging the generosity of the Museum Committee, the Professor 

 reports that he has been very successful in obtaining results of much 

 interest and of great physiological importance. These results, which 

 will shortly be communicated to the Royal Society, show : (1) " That the 

 single intense shock given by the fish owes no small part of its intensity 

 to the fact that the electrical organ itself, apart from the central nervous 

 system, gives a series of rapidly succeeding electrical currents all in the 

 same direction ; (2) That this peripheral organ rhythm occurs at a 

 rate of from 100 to 280 in a second (dependent upon the temperature), 

 so that a single response of the organ, produced by the Central 

 Nervous System, is succeeded by a rapidly following succession ; 

 (3) That the fish is thus able to cause this rapid succession of 

 currents to pass through structures around it without the fatigue 

 which necessarily accompanies an outflow of nerve effort ; (4) That 

 each current in tbe series is similar to its predecessor, and is of 

 small quantity but of high electro-motive force (about 150 volts), and 

 lasts for only -njooths of a second ; (5) That the chief factor in producing 

 this rapid series in the organ is the electrical current itself, which 

 excites the nerve endings in tbe organ. A series of such similar currents 

 in rapid succession has a most marked effect upon animal tissues, and 

 thus the arrangement discovered to exist in the Malapterurus is a 

 particularly favourable one for the purpose for which it is employed by 

 the fish, namely, to protect itself from live enemies and to kill small 



