276 



THE ORGANS 



Nerves of the Stomach and Intestines 



The nerves which supply the stomach and intestines are mainly 

 non-medullated sympathetic fibres. They reach the intestinal walls 

 through the mesentery. In the connective tissue between the two 

 layers of muscle, these fibres are associated with groups of sym- 

 pathetic gangUon cells to form the plexus myentericus or plexus oj 

 Aiierhach. The dendrites of the ganglion cells interlace, forming a 

 large part of the plexus. The axones are grouped together in small 







Fig. 178. — Scheme of Blood-vessels and Lymphatics of Human Small Intestine. 

 (From Bohm and von Davidoff, after Mall.) a, Central lacteal of villus; h, lacteal; c, 

 stroma; d, muscularis mucosae; e, submucosa;/, plexus of lymph vessels; g, circular mus- 

 cle layer; h, plexus of lymph vessels; i, longitudinal muscle layer; j, serous coat; k, vein; 

 I, arter}'; m, base of villus; n, crypt; 0, artery of villus; p, vein of villus; q, epithelium. 



bundles of non-medullated fibres, which pass into the muscular coats, 

 where they form intricate plexuses, from which are given off club- 

 shaped terminals to tne smooth muscle cells. From Auerbach's 

 plexus fibres pass to the submucosa, where they form a similar but 

 finer-meshed, more dehcate plexus, also associated with groups of 

 sympathetic ganglion cells, the plexus of Meissner. Both fibres and 

 cells are smaller than those of Auerbach's plexus. From Meissner's 



