I 9 2 



Niemeyer and his school, that as a rule, only a constitutional 

 debility is transmitted, with a tendency to low forms of 

 inflammation, the products of which rapidly become caseous, 

 and thus lead to tubercle. My own opinion is that a pre- 

 existing condition of scrofula is, in the majority of cases, 

 necessary for the development of tubercle, although what is 

 recognised as scrofulous does not always attain a distinctly 

 tubercular condition. In tubercular as in scrofulous cases, 

 there will usually be found a predisposing as well as an 

 exciting cause the former being hereditary, the latter 

 acquired ; and the higher the degree of hereditary pre- 

 disposition, the less need there will be for an exciting 

 cause. 



Following closely the definitions of Virchow and Billroth, 

 Birch-Hirschfield thus defines scrofulosis : A constitutional 

 anomaly which shows itself by changes, partly of an inflam- 

 matory, partly of a hyperplastic nature, excited in the tissues by 

 a comparatively slight noxious influence changes which are 

 endowed with insufficient recuperative power, and are there- 

 fore prone to lapse into regressive metamorphosis, and 

 following thereupon, into local tuberculosis. Virchow ascribes 

 scrofulosis to " a certain weakness or incompleteness in the 

 structure of the lymphatic glandular apparatus," and accept- 

 ing this theory as far as it goes, we should remember that 

 pathology furnishes us with many proofs as to the dependence 

 of weakness of certain systems and organs on an hereditary 

 predisposition. Thus haemophilia furnishes an example of 

 inherited weakness in the circulatory apparatus. Many 

 other instances might be mentioned. 



Of the causes which give rise to scrofulous constitutions 

 apart from anatomical and physiological conditions, concern- 

 ing which nothing is definitely settled the most important, 



