DIGESTION 



369 



the central nervous system and are at intervals interrupted by a myenteric reflex, 

 which carries the food onwards. 



For further details the reader is referred to the monograph by Cannon (1911). 



FIG. 96. EFFECT ON THE INTESTINE OF STIMULATION OF THE SPLANCHNIC 

 NERVES. Cessation of contractions and relaxation of tone. 



(Bayliss and Starling, 1899, Fig. 16.) 



An interesting point with reference to the ileo-colic sphincter is described by 

 Elliott (1904). The splanchnic nerve, on excitation, causes its muscular cells to 





FIG. 97. EFFECT ON THE INTESTINE OF STIMULATION OF THE VAGUS NERVE. 

 Ninth period of stimulation. Slight preliminary inhibition, followed 

 by powerful contractions, beyond the limit of the recording instrument. 



(Bayliss and Starling, 1899, Fig. 25.) 



contract instead of inhibiting their tone, as it does in the neighbouring parts of 

 the small and large intestines. Adrenaline has the same effect. The significance 

 of this fact in regard to the origin of the alimentary canal will be found in 

 Gaskell's book (1908, p. 449). 



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