234 CHORDATE ANATOMY 



Absorption takes place in the small intestine in accordance with the 

 law of osmosis. The dissolved foods pass through the lining membranes, 

 are taken up by the blood capillaries and the lymphatics, enter the 

 general circulation, and are absorbed into the cells of the various tissues. 



Large Intestine. The large intestine or colon differs from the small 

 not only in its great diameter but also in the absence of villi in the 

 adult. The walls of the large intestine are sacculated, and they bear 

 externally numerous fatty appendages, the appendices epiploicae. The 

 longitudinal muscles do not form a continuous layer as in the small 



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Pig. 220. — A cross section of the human vermiform appendix. Xi5« 



intestine, but are arranged in three longitudinal bands, the teniae. Trans- 

 verse crescentic folds, the plicae semilunares, are abundant. Between 

 these the wall of the colon bulges out to form haustra. 



The large intestine is divided into cecum, vermiform appendix, colon, 

 rectum, and anus. The cecum is a blind sac, about two and a half inches 

 in length, lying near the ileocolic valve in the right ihac fossa. The 

 vermiform appendix of the cecum is an elongated worm-shaped tube 

 between three and four inches in length, attached to the apex of the cecum. 

 The structure of the appendix is similar to that of the large intestine in 

 having numerous Lieberkiihn's glands and lymph nodules. In the 

 majority of persons, the lumen becomes occluded in later life. The 



