CH. XXXV. 



MOVEMENTS OF THE STOMACH. 



523 



inches. The object of this movement appears to be, as just said, 

 to carry the food towards the pylorus as fast as it is formed 

 into chyme, and to propel the chyme into the duodenum; the 

 undigested portions of food are kept back until they are also 

 reduced into chyme, or until all that is digestible has passed out. 

 The action of these fibres is often seen in the contracted state of 



RV 



0.6 



Ret. 



Pig. 414. Very diagrammatic representation of the nerves of the alimentary canal. 

 Oe to Ret, the various parts of the alimentary canal from oesophagus to rectum : 

 L. V, left vagus, ending on front of stomach ; rl, recurrent laryngeal nerve, supplying 

 upper part of oesophagus ; R. V, right vagus, joining left vagus in cesophageal plexus, 

 oe. pi., supplying the posterior part of stomach, and continues as R'V to join the solar 

 plexus, here represented by a single ganglion, and connected with the inferior mesen- 

 teric ganglion m.gl. ; a, branches from the solar plexus to stomach and small intestine, 

 and from the mesenteric ganglia to the large intestine; Spl.maj., large splanchnic 

 nerve, arising from the thoracic ganglia and rami communicantes, r.c, belonging to 

 dorsal nerves from the 6th to the oth (or loth) ; Spl.min., small splanchnic nerve simi- 

 larly from the icth and nth dorsal nerves. These both join the solar plexus, and 

 thence make their way to the alimentary canal ; c.r., nerves from the ganglia, &c., 

 belonging to nth and i2th dorsal and ist and znd lumbar nerves, proceeding to the 

 inferior mesenteric ganglia (or plexus), m.gl., and thence by the hypogastrie nerve, 

 n.hyp., and the hypogawtric plexus, pl.hyp., to the circular muscles of the rectum ; 

 l.r.. nerves from the znd and jrd sacral nerves, 8. 2, 8. 3 (nervi erigentes) proceeding 

 by the hypogastric plexus to the longitudinal muscles of the rectum. (M. roster.) 



the pyloric portion of the stomach after death, when it alone is 

 contracted and firm, while the cardiac portion forms a dilated 

 sac. Sometimes, by a predominant action of strong circular fibres 

 placed between the cardia and pylorus, the two portions, or ends 

 as they are called, of the stomach, are partially separated from 

 each other by a kind of hour-glass contraction. By means of 

 the peristaltic action of the muscular coats of the stomach, not 

 merely is chymified food gradually propelled through the pylorus, 



