462 Miscellaneous. 



always adhere to the ventral surface of the electrical plate, whilst the 

 dorsal surface is completely free. The nervous network of the infe- 

 rior surface forms a very elegant system of regular meshes, which 

 agrees perfectly with the figure given of it by M. Kolliker, and which 

 appears to be intimately united with the substance of the electrical 

 plate. These meshes are of extreme fineness, and can only be distin- 

 guished by means of a high magnifying power. The electrical plate 

 itself (septum of authors) is a perfectly transparent homogeneous 

 plate ; its thickness is only 0001 to - 002 line, and it presents here 

 and there a few scattered nuclei. It is hardly possible to give a po- 

 sitive proof of the continuity of tissue which M. Schultze assumes to 

 exist between this plate and the minute ramifications of the nervous 

 network, for the latter is of extreme tenuity. However, it is impos- 

 sible to separate the nervous network as a continuous layer from the 

 plate. The author depends principally upon chemical considerations 

 in claiming for these plates the part of electrical plates. In fact, 

 they are not formed of conjunctive tissue, but are of an albuminous 

 nature. Under the action of a solution of sugar and sulphuric acid, 

 they acquire a rose-colour, like the electrical plates of other electrical 

 fishes. Ebullition in water, which dissolves the conjunctive tissue of 

 the longitudinal walls of the prisms and the transverse gelatinous 

 septa, separates the plates from each other. These facts are suffi- 

 cient to show that Kolliker was wrong in considering these plates as 

 of the nature of conjunctive tissue. 



Relying on the preceding investigations of R. Wagner and Pacini, 

 without having examined the Torpedo for himself, Bilharz thought 

 that the homogeneous membranes with scattered nuclei, of these 

 fishes, might be compared with the electrical plates of Malapterurus. 

 This assimilation now appears to be well founded. Schultze, like 

 Leydig, certainly shows that not only nuclei but also true cells with 

 a very transparent membrane are found here and there in the homo- 

 geneous plates of the Torpedos, while nuclei alone are met with in 

 the electrical plates of Gymnotus and Malapterarus. But this dif- 

 ference is evidently of no importance. The author thinks, moreover, 

 that these nuclei aud cells are of purely embryonal signification, in- 

 asmuch as these elements would be destined to secrete the funda- 

 mental or essential substance of the plate in which the nervous fibrillse 

 terminate. In this point of view, the electrical plate would only be 

 a kind of tabular development of the axial cylinder. 



The investigations of M. Schultze furnish a new confirmation of 

 the remarkable result previously enunciated by Kupffer and Kefer- 

 stein, that, in all electrical fishes, that face of the electrical plate to 

 which the nerves adhere is turned to the negative, and the free face 

 to the positive side of the fish. 



M. Schultze terminates his memoir with some profound chemical 

 investigations upon the electrical organ of the Torpedos and the 

 pseudo-electric organ of the Rays, Amongst the substances detected 

 we shall indicate, especially, urea in very large quantities, syntonine, 

 and a peculiar albuminous body. — Abhandl. der naturforsch. Ge- 

 sellsch. su Halle, 1859 ; Bibl. de Geneve, 1859, Bull. Sclent, p. 83. 



