558 



THE DIGESTIVE SYSTEM. 



(Fig. 333). These ulcers are usually numerous (Fig. 334) and may be 

 scattered over a large part of the colon. The ulcers are apt to show but 

 little disposition to heal, and the acute colitis often becomes chronic. 



FIG. 334. NODULAR Conns. 

 From the intestine of a child showing numerous ulcers involving solitary nodules. (Compare Fig. 326.) 



Pseudo-membranous (Croupousj Colitis. This form of inflammation may 

 involve the rectum alone, or the entire length of the colon, or only its 

 upper portion. The mucous membrane is congested and swollen, and 

 coated with a layer of false membrane ; the connective tissue between and 

 beneath the gland tubules is infiltrated with fibrin and pus, and in severe 



FIG. 335.-PSErDO-MEMBRA.vOfS (CROUPOVS) COLITIS. 



cases the inflammation involves the muscular and peritoneal coats also. 

 The inflammation is usually more intense at some places than at others, 

 so that the surface of the mucous membrane shows the false membrane 

 in isolated patches. Less frequently there is a uniform coating with the 

 false membrane. In mild cases, as the inflammation subsides, the prod- 

 ucts of inflammation are absorbed and the wall of the intestine returns 



