THE DIGESTIVE SYSTEM. 



563 



may take place from haemorrhoids, and they may afford a portal of entry 

 of bacteria leading to local or general infection. 



THE APPENDIX VEKMIFORMIS. 



Inflammation Appendicitis. Inflammation of the appendix may pre- 

 sent various phases. 



1. The mucous membrane may be the seat of acute catarrhalinflamma- 

 twn. This is of mild type and short duration, with congestion, swelling, 

 and an increased production of mucus ; or it is of severer type, of longer 

 duration, and the cavity of the appendix is distended by mucus and pus. 



2. The entire thickness of the wall of the appendix may be the seat 

 of an acute exudative inflammation. The appendix is very much increased 



FIG. 339. ACUTE SUPPVRATIVK APPENDICITIS. 



Appendix removed by operation twelve hours after flrst symptoms. Streptococcus was found in the 

 exudate. 1, Mucous membrane of the appendix ; 2, lymphatic nodules in the mucous membrane ; 3, sub- 

 mucosa ; 4, muscularis ; 5, mesentery of the appendix ; 6, pus and nbrin covering the appendix ; 7, dense 

 infiltration of the wall of the appendix with pus. 



in size, sometimes to the size of a man's finger. This increase in size is 

 due, not to a dilatation of the cavity of the appendix, but to a thicken- 

 ing of its walls. The walls are congested, swollen, infiltrated with fibrin 

 and pus, the peritoneal coat is covered with fibrin. There is neither 

 necrosis nor perforation. If the appendix is behind the caecum, or if 

 adhesions are formed early, there is only a localized peritonitis. If the 

 appendix projects freely into the peritoneal cavity and no adhesions are 

 formed, a general peritonitis may be soon established. 



3. At one or more points in the wall of the appendix there is an ex- 



