DESCRIPTION OF PLATE IX. 



Fig. I. — Tuberculous pleurisy. Wet preparation stained with 

 methylene blue, showing lymphocytes and red corpuscles. 

 (The nucleoli are not usually so clearly shown, and are not 

 seen in dried films without special staining.) 



Fig. 2. — Pus from knee affected with gonococcal arthritis (early 

 in the disease). The figure will serve to show the appear- 

 ances in an early case of septic pleurisy or empyema. Poly- 

 nuclear cells predominate, but there are a few lymphocytes. 

 The large cells are endothelial, and have ingested some 

 polynuclear leucocytes which show fragmentation of the 

 nucleus. Film dried, fixed with perchloride of mercury, 

 and stained with carbol thionin. 



Fig. 3. — Pus from an old pneumococcic empyema. The cells 

 are polynuclears, but are highly degenerated, and stain very 

 feebly. Stained as in Fig. 2. (All magnified 1000 diameters.) 



