412 OBSEKVATIONS AND EXPERIMENTS 



13. Of the chemical reaction of the electrical organ of the 

 Malaptemrus 1 . 



Max Schultze had stated, when making- observations at Trieste, 

 that the electrical organ of living Torpedos has a distinctly acid 

 reaction 2 . I examined the electrical organ of the Malapterurus 

 repeatedly as to its reaction. In the fresh state, I found it neutral 

 according to the manner of the reaction of muscle, i.e. amphoteric 3 , 

 and only later, from about the third day forwards, distinctly acid. 

 The red spots did not disappear on drying. On the fourth day 

 (in one case) the organ was decidedly in a state of decomposition, 

 and its reaction was alkaline. 



With a fresh organ, on the first day, I examined the effect of 

 higher temperature on the reaction. After keeping it for five 

 minutes in water at 4O-5oC., which by the way leaves the -con- 

 sistency of the organ unaltered, the neutral reaction changed to an 

 acid one. In order, however, that this should appear clearly, the 

 organ must be in contact with the litmus paper longer than frog 

 muscles treated in the same way (see Collected Papers, p. 17). 

 A more important difference between organ and muscle is, that 

 pieces of the organ thrown into boiling water become acid, in- 

 stead of becoming more alkaline like muscles (p. 18). Thus, in 

 this respect, the electrical organ agrees with the nervous central 

 organs, which, according to Funke 4 , also become acid at boiling 

 temperature. But whereas Funke considers that brain and spinal 

 cord become more acid at boiling temperature than at 40-50, the 

 acid reaction of the boiled organ seemed to me less marked than 

 that of the organ heated only 40 or 50 ; this might be considered 

 to indicate a transition to the behaviour of muscles. 



1 With use of my ' Bemerkungen iiber die Eeaction der elektrischen Organe und 

 der Muskeln,' in the Archiv fiir Anatomie, etc., 1859, P- 846. (Comp. above, 

 p. 369.) 



3 Zur Kenntniss der elektrischen Organe der Fische. Zweite Abtheilung, Torpedo, 

 Halle, 1859,4. p. 27. 



8 GesammelteAbhandlungen, note I on p. 10. Comp. Kuhne in Virchow's Archiv fiir 

 pathologische Anatomie, etc., vol. xiv. 1858, p. 328, 334, 345, 347. [Heidenhain has 

 since distinguished this kind of reaction from neutral reaction, as amphichromatic 

 (Mechanische Leistung, etc., p. 153.) Recently, it has been called the amphoteric 

 reaction. Comp. Heintz, Ueber die Ursache der Coagulation des Milchcase'in durch 

 Lab und iiber die sogenannten amphotere Reaction. Journal fiir praktische Chemie, 

 1872, vol. vii. p. 374. It was my friend Heintz, who, in the beginning of my ex- 

 periments on the reaction of muscles, called my attention to the surmise, that in 

 amphoteric reaction, the blue colour would not become red and the red blue, but that 

 both colours would alike become violet ; experiment confirmed this conjecture.] 



* Archiv fiir Anatomie, &c., 1849, P- 841. Comp. Gscheidlen, Timber die chemische 

 Reaction der nervosen Centralorgane. Pfliiger's Archiv, &c., 1874, vol. viii. p. 177. 



