Memoirs: The Autonomic (Enteric) Nervous System of Amphioxus Lanceolatus

Abstract

In this, paper is described a nervous plexus on the wall of the liver and the adjoining parts of the intestine of Amphioxus lanceolatus with numerous stellate ganglion cells, which may be compared with the plexus of Auerbach of the higher vertebrates. A layer of smooth muscle-cells is present, with which the processes of the ganglion cells and the nerve-fibres of the plexus are in synaptic connexion. Covering this layer of smooth muscle-cells a thin layer of connective tissue is present, in which is found a more delicate nervous plexus, connected with the first plexus, analogous to the plexus of Meissner. The nature of the synaptic connexions of the ganglion cells with the pre-ganglionic and post-ganglionic nerve-fibres of the plexus is discussed. The ganglion cells may be compared with the interstitial elements of the sympathetic plexus of the higher vertebrates. The cross-striated trapezius muscle (Legros) is innervated by the same plexus as the muscular coat of the intestine and not by the somatic nerves. The enteric plexus is connected by means of the visceral nerves and dorsal roots with the central nervous system.