UL CERA Tl VE END O CA KDIT/S. 



185 



material, they do not offer the same resistance to the 

 growth of bacteria, when a few reach them, as a healthy 

 cellular tissue does. 



On microscopic examination of the diseased valves the 

 organisms are usually to be found in enormous numbers, 

 sometimes forming an almost continuous layer on the sur- 



p IG 53. Section of a vegetation in ulcerative endocarditis, showing 

 numerous staphylococci lying in the spaces. The lower portion is a frag- 

 ment in process of separation. 



Stained by Gram's method and Bismarck-brown. x 600. 



face, or occurring in large masses or clusters in spaces in 

 the vegetation (Fig. 53). By their action a certain amount 

 of softening or breaking down of the vegetations occurs, 

 and the emboli thus produced act as the carriers of infec- 

 tion to other organs, and give rise to secondary suppura- 

 tions. The kidneys, heart-wall, brain, and spleen are the 



