ON LIVING MALAPTERURUS. 379 



long 1 , is inconvenient on account of its size and the force of its 

 discharges. 



But of the three electrical fishes, it is again the Malapterurus, 

 which is the best suited for all experiments in which the electrical 

 nerves have to be dealt with ; as, for example, when these have to 

 be employed in connexion with the organ, in the same way as a 

 muscle nerve is used in connexion with the muscle. In the Malap- 

 terurus, each lateral half of the organ is provided with a single 

 nerve, which one cut exposes to a considerable length almost with- 

 out bleeding. The electrical nerve is, as it were, already prepared by 

 nature ; indeed the same cut suffices for both nerves. In the Torpedo, 

 each organ contains four, comparatively much shorter nerves, which 

 demand far more skilful preparation and greater injury in order to 

 expose them, than the one nerve in the Malapterurus. Moreover, in 

 the Gymnotus, each half of the chief and accessory organ is provided 

 with over two hundred nerves, all of which it is impossible to pre- 

 pare and deal with experimentally at the same time in the living 

 animal. I do not speak of the unusual interest which the investi- 

 gation of the electrical nerve of the Malapterurus offers on account 

 of its structure, hitherto unique in the animal world, and of its 

 origin from a giant ganglion cell 1 . Add to this, that the tissues of 

 the Malapterurus, inclusive of the electrical organ, appeared to me 

 to possess great tenacity of life, recalling that of the frog. But in 

 order to make the most of these advantages, one must have at com- 

 mand any required number of animals, and this would be possible 

 only in their own home. With two or three fishes, whose life must be 

 spared because much still remains to be ascertained about the living 

 animal, one cannot set on foot researches in which one needs a fresh 

 preparation for almost each experiment, as in the investigation of 

 nerve and muscle. Imagine what it would be in the investigation 

 of nerve and muscle, to be limited to the use of two or three un- 

 injured living frogs. Such a consideration may serve to undeceive 



p. 120), and Saint-Linari (Bibliotheque universelle de Geneve, Avril, 1837, v l- 

 viii. p. 395) kept them alive only five days, Matteucci only three days (Essai sur les 

 Phenomenes electriques des Aniruaux. Paris, 1840, p. 52.) 



1 One might suspect, that in the Gymnotus also, the electrical nerves are the 

 Deiters' processes of as many giant ganglion cells. M. Schultze, however, saw in the 

 electrical nerves, ordinary nerve tubes, and in the anterior half of the spinal-cord, 

 a remarkable number of large ganglion cells (Zur Kenntniss der elektrischen Organe 

 der Fische. Specially reprinted from the 4th vol. of Abhandlungen der Naturfor- 

 schenden Gesellschaft in Halle, 1858, pp. 30, 32, 33). This leads us rather to infer 

 the existence of a structure similar to that of the Lobus electricus in the brain of the 

 Torpedo '(comp. M. Keichenheim in the Archiv fur Anatomie, etc., 1873, p. 751). 



