. On the anatomy of vertebrates. Vertebrates; Anatomy, Comparative; 1866. 352 ANATOMY OF VERTEBRATES. most characteristid feature of tlie organisation of the electric battery is its enormous suj^ply of nervous matter. Each organ derives tliis supply from one branch of the trigeminal, fig. 231, a, and from four branches of the vagal nerves, ib., b, c, d ; the four anterior nerves are each as thick as the sjDinal cord: the last nerve is a feeble branch of the vagus. The trigeminal and vagal enlargements of the olivary and restiform tracts coalesce on each side, forming the so-called ' electric l
. On the anatomy of vertebrates. Vertebrates; Anatomy, Comparative; 1866. 352 ANATOMY OF VERTEBRATES. most characteristid feature of tlie organisation of the electric battery is its enormous suj^ply of nervous matter. Each organ derives tliis supply from one branch of the trigeminal, fig. 231, a, and from four branches of the vagal nerves, ib., b, c, d ; the four anterior nerves are each as thick as the sjDinal cord: the last nerve is a feeble branch of the vagus. The trigeminal and vagal enlargements of the olivary and restiform tracts coalesce on each side, forming the so-called ' electric lobes' of the medulla oblongata. The electric branch of the nerve may be defined even at its origin, from the true ganglionic part of that nerve; and both this and the vagal branches consist entirely of the pri- mitive nerve-fibres of animal life, as in fig. 164. The nerve- trunks are distributed by successive resolution into smaller and smaller fasciculi, until they finally penetrate tlie septa of the columns, and terminate thereon by meshes formed by loops, or by the return and anastomosis of the primitive nerve-fibres.' In the eel-like Gymnotus the electric organs are four in number, and are situated two on each side the body, extending from behind the pectoral fins to near the end of the tail, fig. 232, 232. Right electrical organs, G;/7)nio/»s (reduced), ccxvil. /(, I. They occupy and almost constitute the whole lower half of the trunk, fig. 233; the upper organ, ib. h, being much larger than the lower one, ib. i, from which it is separated by a thin muscular and aponeurotic stratum. The organs of one side are separated from those of the other, above by the vertebral column and its muscles, ib. c, then by the air-bladder, ib. d, and below this by an aponeurotic septum, ib. /(. From this septum, and from that covering the air-bladder, there extend outward, to be attached to tlie skui, a series of horizontal, or nearly horizontal, membranes, arranged in the longitudin
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