CYTO-DIAGNOSIS 



297 



arranged in masses, are mixed with red corpuscles, and per- 

 haps a leucocyte or two. 



Some writers consider these cells to be growth-cells, but 

 on what grounds I do not know. When they form masses 

 they are always one cell thick, never solid alveoli; and, more 

 conclusive, when an opportunity is obtained of examining the 

 cells of the growth post-mortem, they are often absolutely 

 different from those found in the exudate during life. 



In yet other cases the endothelial cells are of the ordinary 

 passive type, but a suspicion of the nature of the growth may 

 be obtained from the number of red corpuscles present. 



FIG. 55. MALIGNANT MASSES IN ASCITIC FLUID. 



"MECHANICAL" EXUDATES (i.e., those due to cardiac disease, 

 pulmonary congestion, or renal disease). The deposit from 

 the exudate is usually very scanty, and consists of large flat 

 masses of passive endothelial cells, there being often many 

 cells in one large plate; their outlines may be indistinct. 

 There is usually nothing else, but there may be a few red cor- 

 puscles or leucocytes. 



PLEURISY SECONDARY TO INFARCTS. Endothelial cells 

 mixed with much blood and with many polynuclear leucocytes 

 have been described, but T have no personal experience of 

 the condition. 



