THE GASTRIC JUICE 321 



observations strongly indicate that the act is a nervous phenomenon, at least 

 under nervous control. 



Quite recently Pawlow has proved that secretory fibers are carried 

 to the gastric glands in the vagus trunk. His experiment consisted in 

 establishing a gastric fistula, and some days later in dividing the esophagus 

 in the neck in such a manner that any food swallowed would be diverted 

 to the exterior through the cut end. A "fictitious meal" could then be given 

 to the animal, and the effect upon the stomach noted. As long as the vagi 

 were intact, certain foods (meats) caused a flow of gastric juice, though 

 none of the food reached the stomach. The secretion of gastric juice con- 

 tinued for hours with the production of a large quantity of secretion. When 



PIG. 259. Very Diagrammatic Representation of the Nerves of the Alimentary Canal. Oe to 

 Ret, the various parts of the alimentary canal from esophagus to rectum; L. V., left vagus, ending on 

 front of stomach; rl, recurrent laryngeal nerve, supplying upper part of esophagus; R. V, right 

 vagus, joining left vagus in esophageal 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 mesenteric 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 gth (or loth); Spl. min., small splanchnic nerve similarly 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, etc., belonging to nth and i2th dorsal and ist and zd lum- 

 bar nerves, proceeding to the inferior mesenteric ganglia (or plexus), m. gl., and thence by the hypo- 

 gastric nerve, n. hyp., and the hypogastric nerve, n. hyp., and the hypogastric plexus, pi. hyp., to the 

 circular muscles of the rectum; /, r., nerves from the 2d and 3d sacral nerves, S. 2, S. 3 (nervi 

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

 Foster.) 



the vagi had been cut, no secretion occurred. Moreover, he found that direct 

 stimulation of the vagus produced a flow of gastric juice. 



Khigine placed foods in an isolated gastric pouch prepared with care to 

 maintain the nervous relations intact, and it led to secretion of gastric juice 

 in the main part of the stomach. This is undoubtedly a nervous reflex effect. 

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