BipMheritie Memhrane and the Croupous Cast. 79 



as to tlieir exact etiology, proceeding to treat tliem in opposite ways. 

 Sir Thomas Watson, in the last edition of his ' Practice of Physic,' 

 seems to give in his adhesion to the unity of all membranous affec- 

 tions. I doubt very much whether he is right ; he is, probably, far 

 nearer the truth in separating catarrhal croup, or simple laryn- 

 gitis, although during life the symptoms are not distinguishable. 

 His division of this disease is as follows : — 



Croup I Membranous { Simple f 



Catarrhal 



3 < Simple f 

 I Diphtheritic \ 



or the same. 



Diphtheritic ! Qy. distinct 



And for the first time he gives a place to diphtheria, and says of it, 

 that " the proper place for this disease in any methodical nosology 

 would be among the specific fevers." In. the new nomenclature of 

 diseases, drawn up under the sanction of the College of Physicians, 

 croup and diphtheria are classed under one heading, the latter as a 

 disease " not local," and requiring " a definition " ; while both are 

 separated from laryngeal catarrh, laryngitis, and laryngismus 

 siridtdus. 



The epidemic visitation of diphtheria during the years 1858 and 

 1859, for the first time attracted the attention of the profession to 

 the pathological indications and histological anatomy of the false 

 membrane. Members of the Pathological Society of London at the 

 period exhibited specimens of membranous exudations. A few 

 microscopical examinations were made ; these in my opinion were 

 somewhat unsatisfactory, or, at all events, not at all conclusive as 

 to the pathology of the disease ; indeed it was by no means made 

 clear that any considerable difference exists between the mem- 

 brane, nearly always associated with diphtheria, and the mucus 

 or albuminous film thrown off in certain croupous affections of the 

 throat, and it seems hard to comprehend that, while the patholo- 

 gical indications in the one case partakes of an inflammatory 

 nature, in the other it is a simple ??o«-inflammatory tenacious 

 exudation of little importance. 



Conflicting statements, therefore, appear in the writings of 

 those who exhibited various specimens at the meetings of the 

 Society ; as, for instance, " the false membrane was made up of a 

 network of fribrillated lymph, in which epithelium was entangled " ; 

 and then, again, as if in seeming contradiction, " only a very 

 delicate film, in which quantities of cells and granules are entangled, 

 but nothing like a fribrillated structure was found." The expla- 

 nation of this divergence of opinion is only explicable on the sup- 

 position that no one then had a notion of the true relation of the 

 '^ felt-lihe" membrane to a specific form of disease, or that the 

 histological characters of the membrane were totally unlike those of 

 the simple and almost structureless film thrown off during a non- 



