180 



THE DIGESTIVE SYSTEM 



times to give rise to cells replacing worn-out goblet cells. The 

 goblet cells of glands secrete mucus to lubricate the intestinal 

 lumen surface, and thus aid in the passage of the fecal material 



Mucos 



Subniucosa 



Musculuris 



Adventiiia 



Fig. 115. — Diagram of large intestine of mammals. 



which becomes more solid, due to absorption of water through the 

 intestinal wall. 



The wall of the cecum usually has lymph nodules in the sub- 

 mucosa. In some forms, as in the rabbit, these nodules may encircle 



Fig. 110.— Photograph of the ileocecal junction of the cat, showing the valve and 

 the appendix, 3; 1, ileum; 2, cecum. 



the lumen and forui the greater ])art of the wall with a reduction in 

 amount of coimective tissue and mu.scularis. 



The vermiform appendix is a blind pouch extending from the end 

 of the cecum at its junction with the small intestine. (Fig. IIG.) 



