CROUPOUS INFLAMMATION. 421 



These orifices are generally round and open ; they are now 

 stopped up and distorted by the swelling. 



§ 361. Similar conditions are never met with in the other 

 follicular glands of the alimentary tract. On the other hand we 

 sometimes find, in persons who are especially predisposed, a 

 very singular and important phenomenon : organic inflamma- 

 tions in general, but particularly catarrhal affections of the 

 mucous membranes, causing an enlargement of those lymphatic 

 glands which are nearest the seat of mischief, an enlargement 

 differing from that " acute swelling " which I have already 

 described, by its gradual progress and its obstinacy, and differ- 

 ing from true hypertrophy, by the exclusive proliferation of the 

 corpuscular elements, and the consequent disorganisation of the 

 entire gland ; distinguished moreover from both alike, by the 

 enormous size to which the gland may attain. I refer to 

 the scrofulous or cheesy degeneration described in § 203 et seqq. , 

 which, when restricted to the mesenteric glands, gives rise to the 

 symptomatic aggregate known as Tabes mesenterica. Some- 

 times indeed, it occurs in the solitary and agminated follicles of 

 the intestine; but these are so intimately connected with " tuber- 

 culous" degeneration of the intestinal mucous membrane, and so 

 constantly associated with it, that it would be inconvenient to 

 treat of them apart. (^See Tuberculosis of mucous membranes.) 



2. Croupous Inflammation (Inflammatio pseudo-memhranacea). 



§ 362. Croupous inflammation of a mucous membrane differs 

 from catarrhal inflammation in one essential particular only. 

 The hyperasmia and swelling may be more intense ; but it is 

 only in the inflammatory products, that we can discover any 

 qualitative difference. These j^roducts exhibit the naked-eye 

 characters of a coagulated albuminous substance ; they take 

 their name of "fibrin," or "fibrinous exudation," from the 

 chief representative of spontaneously coagulable substances. 

 The material in question is yellowish-white, tough and elastic ; 

 when stretched, it is not drawn out into threads, but gives way 

 suddenly and is torn across. On the addition of acetic acid, 

 it clears up and swells like fibrin ; its reaction therefore is 

 precisely the opposite of that of mucus, which is rendered 

 opaque and ropy by acetic acid. Morphologically too, the 



