84 



THE VERTEBRATE ANIMAL: METABOLISM 



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Fig. 48. — To illustrate the muscular activities of the small intestuie. 



The three upper drawings represent a particular region of the intestine at successive 

 periods during segmentation. The three lower drawings show a particular region of the 

 intestine at successive periods during peristalsis. Arrows within the tube snow direction 

 of movement of food contents. Arrows between drawings call attention to changes in 

 wall of intestine. The vertical dotted lines in upper drawings indicate places of following 

 contractions. 



