DISEASES OP THE HEAUT.— ENDOCARDITIS. 279 



Both cases occurred in children, in connexion with acute miliary 

 tuberculosis of all the serous membranes and the pia mater. 



§ 247. The large cheesy nodules in the myocardium which 

 used formerly to lie called "tubercles of the heart" are in all 

 probability, as Virchow has recently shown, not tuberculous but 

 S3q)hilitic. 



Gummata of the heart are most commonly found in the 

 septum between the ventricles. As a general rule, several 

 nodules not larger than a pea are held together by a quantity of 

 inflammatory connective tissue, forming a single tuberculated 

 mass; we do however find solitary nodules of so remarkable 

 a size, that they protrude into the cavity of both ventricles at 

 once. 



§ 248. Cancerous nodules — secondary to medullary or me- 

 lanotic growths elsewhere — seldom grow to any size in the heart. 

 We rarely find them larger than a hazel-nut. They all originate 

 in the connective tissue of the myocardium, and force their way, 

 according to their position, either inwards or outwards ; in the 

 former case, they detach and occasionally perforate the endocar- 

 dium, in the latter, they do the same to the pericardium. It has 

 also been asserted that thrombi of the heart's cavities (polypi of 

 the heart) are susceptible of undergoing cancerous degeneration ; 

 but this assertion is grievously in need of being corroborated. 



/8. Endocardium. 

 A. Acute Endocarditis. 



§ 249i Attention has already been drawn to the fact that the 

 endocardium, although the analogue of the internal coat of the' 

 vessels, is yet far more delicate in its texture ; that it contains 

 vessels — at least here and there ; that where these are lacking, 

 the rich vascular network of the myocardium sends its terminal 

 loops close under the thin lining membrane, so that we may 

 regard the latter as standing in direct connexion wdtli the vasa 

 rasorum. We cannot therefore be surprised to find that the 

 endocardium is far more susceptible than the tunica intima of 

 the vessels. Various anomalies in the composition of the blood, 

 the py^emic, puerperal and typhous dyscrasi^ — but above all, 

 the dyscrasia associated with acute articular rheumatism, act as 



