THE DIGrESTIA^E SYSTEM. 



555 



(a) AMCEBIC COLITIS. This form of colitis is apparently incited by 

 the presence in the wall of the intestine of the Amoeba coli. 



The anicebae are found in the gelatinous masses which are common in 

 the stools. They are of rounded shape, and, when alive, change their 

 position and shoot out and retract little projections (pseudopodia). 



FIG. 330A. ACUTE CATARRHAL COLITIS. 



The epithelium of the tubular glands, especially near their mouths, is forming an excessive amount of 

 mucus with destruction and exfoliation of the cells. The tubules are dilated with mucus which covers the 

 surface. The mucosa at the right is necrotic and forms the edge of an ulcerated area. 



Their outer portion is composed of a pale hyaline or homogeneous sub- 

 stance; the inner contains vacuoles and is more refractive (see page 129). 

 In the colon the amoebae are found in the connective-tissue coat (Fig. 

 331 ) and in the floors of the ulcers. 



FIG. 331.-AMOCBIC COLITIS. 

 Showing amoebae in the submucous flbrous 



