190 PHYSIOLOGY CHAP. 



after which its movements diminish, and are finally abolished 

 (Fig. 64). 



Fio. 64. Tracings of pyloric rhythm and its variations under the influence of progressive incre- 

 ments of pressure. (Ducceschi.) At 1, the exploring balloon exerted very weak pressure on 

 the walls of the antrum ; at 2, the pressure was increased by addition of 50 c.c. water ; at 3, 

 4, 5, 6, 7, respectively, 50 c.c. water were added, by which the balloon became more and more 

 distended. 



On exciting the stomach by a sound with a rough surface, 

 peristaltic movements are set up in the cardiac portion and fundus ; 

 in the region of the pyloric antrum, on the contrary, the rhythm 



