<P> Although the large intestine has peristalsis of the type that the small intestine uses, it is not the primary propulsion . Instead, general contractions called mass movements occur one to three times per day in the large intestine, propelling the chyme toward the rectum . Mass movements often tend to be triggered by meals, as the presence of chyme in the stomach and duodenum prompts them . </P> <P> The human lymphatic system has no central pump . Instead, lymph circulates through peristalsis in the lymph capillaries, as well as valves in the capillaries, compression during contraction of adjacent skeletal muscle, and arterial pulsation . </P> <P> During ejaculation, the smooth muscle in the walls of the vas deferens contracts reflexively in peristalsis, propelling sperm from the testicles to the urethra . </P> <P> The earthworm is a limbless annelid worm with a hydrostatic skeleton that moves by peristalsis . Its hydrostatic skeleton consists of a fluid - filled body cavity surrounded by an extensible body wall . The worm moves by radially constricting the anterior portion of its body, resulting in an increase in length via hydrostatic pressure . This constricted region propagates posteriorly along the worm's body . As a result, each segment is extended forward, then relaxes and re-contacts the substrate, with hair - like setae preventing backwards slipping . </P>

Which one of the following does not occur during swallowing