. Electro-physiology. Electrophysiology. 382 ELECTRO-PHYSIOLOGY CHAP. long, narrow, still plainly striated stalk to the plate-rudiment, which has meantime increased considerably in breadth owing to proliferation of nuclei. Its ventral half consists of an almost transparent plasma traversed by little fibres (muscle-fibrils?), while the characteristic rounded nuclei lie in a finely granulated dorsal stratum (Babuchin, Fig. 249, e). An isolated column at this stage consists of thick loaf-shaped bodies, not perfectly regular, and separated by embryonic cells. These do not take up the entire width
. Electro-physiology. Electrophysiology. 382 ELECTRO-PHYSIOLOGY CHAP. long, narrow, still plainly striated stalk to the plate-rudiment, which has meantime increased considerably in breadth owing to proliferation of nuclei. Its ventral half consists of an almost transparent plasma traversed by little fibres (muscle-fibrils?), while the characteristic rounded nuclei lie in a finely granulated dorsal stratum (Babuchin, Fig. 249, e). An isolated column at this stage consists of thick loaf-shaped bodies, not perfectly regular, and separated by embryonic cells. These do not take up the entire width of the column, but lie near and over each ; The stalks (remains of primitive muscle-fibres) are often attached laterally to the plate-rudiment, and become steadily thinner, subserviently disappearing altogether, while the latter now finally assume the shape of very thin plates, and fill up the entire cross - section of the column. Isolation of the plates is very difficult at this stage, seeing that the external border cells gradually coalesce into a firm sheath of connective tissue round the electrical prisms. Little as the structure of a complete column of Torpedo recalls a striated muscle structure, there cannot, in view of the above facts, be the slightest doubt as to the genetic relations between the two tissues, and one of the most significant advances, not merely in the FIG. 250.— of embryonic column . , . ., 1-1 n of Toledo. P = rudiment of anatomy, but also in the physiology ot plate. (Babuchin.) t]ie eiectrical organ, was the discovery by Babuchin of this connection. As Engelmann remarks (8, p. 149), " oSTowhere else in nature have we, side by side, and so completely accessible to research, the anatomical and physiological factors for the vital production of mechanical and electrical ; Unfortunately all attempts made by C. Sachs to determine the embryonic development of the organ of Gymnotus were fruitless, and we can only conjecture t
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