Tin: mi - ii INISMS 01 DI( 



• if them a rhythmic to-and Pro shifting of the ma* •«! along the 



Lumen of the gut, rapidly repeated for man; minut 



When the intestines are floated oul in a warm bath • solution, 



it is Been thai the rhythmic segmentation i narrow ri 



contraction. Under such conditions also it is often noted that 

 loops i>f intestine sway from side to Bide The balloon method a 

 veals the presence of slighl waves of contraction thai pass rapidly all 

 the gut, and follow each other al the rate of twel . |>'-r min 



Both i>t' tlic muscular coats of the intestine are involved, and it i-> b< 

 thai the contractions are responsible nol only for the pendular m< 

 Hunts but for the rhythmic segmentation observed by tl • y method. 



Aecording to this view these movements ai stantly p 



the intestine, and become exaggerated by the mechanical Btimulus which 

 is offered by the masses of food to such an extenl thai they divide the 

 masses into portions. The evidence for this belief rests on the fad thai 



;fdoc56 9 b° b c 



Fig. 161. — Diagrammatic representation of i in the inl An 



unbroken shadow is shown in / and its segmentation in .'. The < 1> >t i c-. 1 I 

 slinw the position of division and in J is - 

 column together. U'roni Cannon.) 



when tin 1 contraction is studied by the balloon method, it becomes mar 

 over the middle of the balloon, where the greatest tension i \ sts 

 Several functions can be assigned to these movements. Ti 



intimate mixture of the £ 1 with the digestive juices, and by bring 



ever new portions of food in contacl with the m they 



absorption. They also have an importanl massaging influen >n 



blood and lymph in the vessels of the intestinal walls I 

 Bage of lymph from the lacteals into the m< c lymphat 



depend very largely upon these movemei 



Tli: I'l RI8TA1 TIC MOVI MEN1 



Tl ther movemenl observed in the small intestine is thai 



peristaltic wave. It occurs in two forms: I ely ad '>n- 



traction I 1 to 2 cm. per minute , p d by an inhibiti dls. 



and proceeding only through a short distance in a and 



