. Electro-physiology. Electrophysiology. 374 ELECTRO-PHYSIOLOGY CHAP. seen from the surface) first described in detail by Boll for Torpedo. The nerve-ending itself presents, according to Sachs, a varying aspect "resembling now Kuhne's end-plate, and now Schultze's ; According to Fritsch, the thorn-like papillae are to be viewed as the real bearers of the nerve-endings in the Gymnotus plates. " Upon these there are comparatively coarse prolongations of the axis-cylinder," so that they are "allied to the stalk of the Malapterurus ; As regards the indisputa
. Electro-physiology. Electrophysiology. 374 ELECTRO-PHYSIOLOGY CHAP. seen from the surface) first described in detail by Boll for Torpedo. The nerve-ending itself presents, according to Sachs, a varying aspect "resembling now Kuhne's end-plate, and now Schultze's ; According to Fritsch, the thorn-like papillae are to be viewed as the real bearers of the nerve-endings in the Gymnotus plates. " Upon these there are comparatively coarse prolongations of the axis-cylinder," so that they are "allied to the stalk of the Malapterurus ; As regards the indisputable genetic relation between the electrical organs and striated muscle, it may be conjectured that the mode of ending of the nerve in the sub- stance of the plate is analogous to that of Torpedo, although the observations made up to this time afford no positive evidence of it. The plates in the wide compart- ments of Sachs' columns are dis- tinguished from the others mainly the greater lensth of the. p p FIG. 243.—One wide and two narrow compart- by ments of Gymnotus, seen in cross-section • M1 /T-,. 0 . 0. (as in Fig. 241) under a high power, with anterior papillae (Fig. 243), 111 enclosed plates (P). (DU Bois-Reymond.) which, moreover, in the fresh state, Sachs observed a broad, dim cross-striation and traces of double refraction, in the axis or at the margin. If the final distribution of the nerve in the peripheral organ (electrical plates) is thus uncertain, no such doubt exists as to the central origin and coarser anatomical structure of the electrical nerves. Valentin, reasoning from a likeness (afterwards proved to be inadequate) between the brain of Gymnotus and that of the eel, assumed a certain section of it (by analogy with Torpedo} to be the electrical lobe, and centre whence spring the electrical nerves. Later investigations, however, showed the part of the brain in question to be identical with the cerebellum so markedly developed in the allied cat-fish (Silur
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