The involuntary nervous system / by Walter Holbrook Gaskell.

  • W. H. Gaskell
Date:
1920
Catalogue details

Licence: In copyright

Credit: The involuntary nervous system / by Walter Holbrook Gaskell. Source: Wellcome Collection.

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    All these collateral ganglionic masses are connected with the central nervous system by means of the splanchnic nerves. It was once thought that, just as the rami communicantes connected the central nervous system with the ganglia of the lateral chain, so the splanchnics connected the ganglia of the lateral chain with the collateral ganglionic masses. Milne Edwards gave the name rami efferentes to the whole set of nerves, which were held to connect these two groups. There is, however, in reality no such connexion, the splanchnic nerves are simply rami communicantes direct from the central nervous system to the cells of the col¬ lateral chain, the fibres of which lie along the lateral or main chain for part of their course and so appear to spring from the ganglia of that chain. The splanchnic nerves are divided into two very distinct groups, an upper or superior group, which contains the largest nerve—the splanchnic nerve proper—and connects with the superior mesenteric, semilunar, and renal ganglia, and a lower or inferior group, consisting of three to four nerves which connect with the inferior mesenteric ganglion. The whole set may be called the abdominal splanchnic nerves, and in consider¬ ation of their relation to the roots of the spinal cord it is often convenient to speak of the superior group as the thoracic splanchnics and of the inferior group as the lumbar splanchnics. The lateral ganglia (Fig. 4) form a segmentally arranged chain corresponding to the segmental spinal nerves, each ganglion sending sympathetic fibres to its corresponding nerve and to its corresponding spinal segment. The upper ganglia in the thoracic region have become fused to form the large ganglion stellatum ; and the ganglia of the cervical region have fused to form the inferior and superior cervical ganglia, the latter of which supplies the three foremost cervical nerves, the rest being supplied by sympathetic fibres from the inferior cervical ganglion and from the ramus vertebralis, a striking grey ramus from the ganglion stellatum, which supplies the four lower cervical nerves and corresponding spinal segments. The evidence up to this point is clear, that the so-called sym¬ pathetic system consists of an outflow from the spinal cord of fine medullated efflerent nerves, which terminate in or around nerve cells, whose fibres (sympathetic or post-ganglionic) proceed to and supply the peripheral organs. Although I was strongly
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