. Animal physiology. Physiology, Comparative; Physiology, Comparative. ELECTRIC FISHES. 323 forming two large masses, which extend backwards and out- wards from each side of the head. They are composed of two layers of membrane, the space between which is divided by vertical partitions, into hexagonal cells like those of a honey- comb (0, Fig. 167), the ends of which are directed towards the two surfaces of the body. These cells,—which are filled with a whitish soft pulp, somewhat resembling the substance of the brain, but containing more water,—are again subdivided horizontally by little memb
. Animal physiology. Physiology, Comparative; Physiology, Comparative. ELECTRIC FISHES. 323 forming two large masses, which extend backwards and out- wards from each side of the head. They are composed of two layers of membrane, the space between which is divided by vertical partitions, into hexagonal cells like those of a honey- comb (0, Fig. 167), the ends of which are directed towards the two surfaces of the body. These cells,—which are filled with a whitish soft pulp, somewhat resembling the substance of the brain, but containing more water,—are again subdivided horizontally by little membranous partitions; and all these partitions are profusely supplied with vessels and nerves. The electrical organs of the Gymnotus are essentially the same in structure, but differ in shape in accordance with the conformation of the animal; they occupy one-third of its whole bulk, and run nearly along its entire length, being arranged in two distinct pairs, one much larger than the other. In the Malapterurus, there is not. Fig. 168-—Electric Malapterurus. any electrical organ so definite as those just described; but the thick layer of dense areolar tissue, which completely surrounds the body, appears to be subservient to this function,—being composed of tendinous fibres interwoven together, and contain- ing a gelatinous substance in its interstices, so as to bear a close analogy with the special organs of the Torpedo and Gymnotus. 423. In all these instances, the electrical organs are supplied with nerves of very great size, larger than any others in the same animals, and larger than any nerves in other animals of like bulk. These nerves arise from the top of the spinal cord, and seem analogous to the pneumogastric nerve (§. 458) of other animals. The influence of these nerves is essential to the action of the electric organs. If all the trunks on one side be cut, the power of the corresponding organ will be destroyed, but that of. Please note that these images are extr
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