INFLAMMATION. 423 



more particularly concerns the invaded tissues themselves. They 

 are first reduced to their juvenile condition; their medullary 

 elements, by endogenous or exogenous new formation or simple 

 division, give rise to a new formation of inflammatory corpus- 

 cles. If these remain interconnected, a new formation of tissues, 

 in most instances, and most predominantly of connective tissue, 

 takes place; thus, "hypertrophy" or " hyperplasia " is estab- 

 lished. If, on the contrary, the inflammatory corpuscles become 

 separated, pus-corpuscles arise from the inflamed tissue, either 

 forming an abscess or leading to pyorrhoea or empyema. The 

 question, how many of the pus-corpuscles owe their origin to 

 emigration of colorless blood-corpuscles, cannot be answered 

 positively. 



Considering both the nature of the exudation and the tissue 

 changes, there is no good reason to abandon the old terminology 

 of "humoral pathology " for the designation of different forms of 

 inflammation such as catarrhal, croupous, etc. These, it is true, 

 differ only in degree, but the names, having been once adopted, 

 may be used, as heretofore. 



(a) Catarrhal inflammation consists of a serous exudation, a 

 partial reduction of the connective tissue into its juvenile con- 

 dition, an increased secretion, proliferation, and shedding of the 

 epithelia. In acute catarrhal inflammation the predominant feat- 

 ures are the serous exudation, the augmented secretion, and shed- 

 ding of the epithelia from the free surfaces and in glandular 

 organs ; there is, in addition, a hyperaemia of the subjacent con- 

 nective tissue. In subacute or chronic catarrhal inflammation the 

 augmented secretion and shedding of the epithelia persists, and 

 the subjacent connective tissue is hypertrophied, with a more or 

 less new formation of blood-vessels, or, on the contrary, reduced 

 in bulk atrophy. In closed or occluded glandular cavities the 

 epithelia are transformed into medullary 'corpuscles, from which 

 new connective tissue arises cirrhosis. 



(~b) Croupous inflammation consists of a fibrinous exudation 

 and a partial reduction of the connective tissue into its juvenile 

 condition, while the epithelia, by their imbibition of the fibrinous 

 exudate, are destroyed. In acute croupous inflammation the exu- 

 date is sometimes fibrinous, sometimes modified albuminous. On 

 free mucous surfaces and in glandular organs the epithelia are 

 destroyed ; these, with intense hyperasmia, haemorrhage, and 

 inflammation of the connective tissue, are the main symptoms. 

 In subacute or chronic croupous inflammation the exudation is 



