426 



MTJCOTJS MEMBRANES, 



§ 366. The intimate connexion between the secreted products 

 and the secreting surface in pharjaigeal croup, is the cause of the 

 close adhesion between them at the outset of the disease. When 

 the normal state is re-established, the morbid cell-metamorphosis 

 comes to an end ; the cells secreted by the mucous membrane 

 remain unaltered, forming, together with a small quantity of 

 serum which is simultaneously poured out, a thin layer of puru- 

 lent fluid ; and this of itself involves the detachment of the false 

 membrane. 



Notwithstanding the superficial character of pharyngeal 

 croup, it is a very dangerous affection, owing partly to the 



Fig. 123. 



Fibrinous degeneration of pavement- cells (after E. Wagner). 



constitutional disturbance which attends it, partly to the risk of 

 larpigeal complications ; the pharyngeal angina being associated 

 with a laryngeal angina, due to a swelling of the submucous 

 connective tissue, which may assume alarming proportions. 



§ 367. Croupous inflammation of the larynx and trachea 

 presents us with a serial succession of simple catarrh and pseudo- 

 membranous exudation. Even in its catarrhal stage it is capable 

 of giving rise to the familiar group of symptoms in their highest 

 intensity — nay, even to death itself. The laryngeal mucous 

 membrane is acutely inflamed, and proportionately swollen ; it 

 secretes a viscid and tenacious mucus, rich in cells ; this forms 

 a thick, adhesive, yellowish layer, contracting the already nar- 

 row chink of the glottis to such a degree, that we need hardly 



