480 LIVING TORPEDOS IN BERLIN. 



captivity, especially during- the summer. In the summer of 1883, 

 when they reached here earlier, they had kept in comparatively 

 good health. The fish of the spring- consignment in 1884 re- 

 mained indeed quiet, buried in the gravel a position which they 

 abandoned as soon as they became seriously ill (p. 419) ; they 

 looked quite well, breathed reg-ularly, and struggled vigorously 

 when lifted up by the tail. But they gave shocks only after 

 repeated violent stimulation, and their electrical force was so much 

 lowered that on July 29th I did not succeed in making the shock 

 of the fourth torpedo perceptible to my audience in the manner 

 described in my former paper. The condition of the organ 

 corresponded obviously to its impaired functional activity, just as is 

 the case with frog preparations which do not react well *. The organ 

 was soft, deliquescent, drops of liquid exuded from the cut surfaces, 

 and as it had lost its plumpness the organ preparations could not 

 be made so well as before. Its organ current appeared also less 

 strong and showed peculiar irregularities (see below, 2). The 

 cause of this was undoubtedly that the fish fasted at a com- 

 paratively high temperature, but up to this time no mode of feeding 

 them had been discovered (p. 419). The keepers fancied that the 

 seventh torpedo, which had lived in the Aquarium the whole 

 previous winter, more than half the year, had taken nourishment. 

 They inferred this only from its apparently vigorous condition, but 

 I found the stomach and intestine quite empty. 



Fish kept in winter at only 1 0-5-1 2C. certainly suffer less in 

 confinement than summer fish. However, judging from their 

 electrical functional activity, they also are far from the normal 

 condition 2 . Even when put into warm sea- water but twenty-four 

 hours before the experiments, they gave feeble shocks only, and only 

 on strong excitation. 



The field of our experiments on electrical fishes is much within 

 the limit beyond which the greatest amount of functional activity 

 becomes indispensable, and in spite of the bad condition of several 

 preparations, I succeeded, as I believe, in attaining some not unim- 

 portant results. I purpose to communicate these now, without 

 awaiting further consignments, as their safe arrival depends more 

 or less upon chance. On the other hand, the deficiency of 

 functional activity undoubtedly had for result, that certain other 

 questions could not be completely settled. I will however speak 



1 Untersuchungen fiber thierische Elektricitat, vol. ii. pt. i. p. 168. 



2 Comp. i. p. 121 ; Untersuchungen, etc., p. 266. 



