14 



The heart blood was always well coagulated, the spleen small and normal, 

 the liver normal or enlarged, with fatty degeneration. 



Croupous and Diphtheritic Membranes 



Croupous and Diphtheritic Membranes. The pathologic anatomical con- 

 ditions of the pseudo-membranes in mouth, eyes, etc., varied considerably. The 

 small, grey, thin pellicles, which are often the first stage of the membranes, 

 were found to be the outer epithelial-layers mingled witli leucocytes. Sections 

 of the epithelial-layers showed these to be more or less invaded by leucocytes, 

 while the submucous tissue usually seemed intact. In all more severe cases, 

 however, the loose, submucous tissue was completely filled up with leucocytes. 

 The epithelial layer underwent changes, especially in the middle layer. The 

 epithelial cells were dislodged from their normal position by fibrinous putrid 

 exudation (Fig. 2). They lost their contour, and the protoplasm became 









Figs. 12 and 13.— The Roup bacillus (Z>. cocoxiiius) iiu\<j;nified about S50. The bacillus 

 is stained with srentian violet, the flagella by Van Ernies^eni's method. 



cloudy or decayed to a granular detritus. The cell-nuclei swelled till they be- 

 came two to six times their normal size, and the contents of the nuclei became 

 homogenous and were difficult to stain, except one or two round, central or 

 excentric nucleoli. 



O'ften, too. tlie plasm of tlie nucleus became a fine granular detritus. These 

 granules could then be deeply stained. The abnormal nuclei remained round 

 and sharply outlined by thin nuclear membranes. They appeared like foreign 

 bodies, and have usually been pronounced to be protozoa. Fig 3 shows these 

 transformed nuclei, in which the edges of the separate cells have completelv 

 vanished and changed to a partly granular, partly turbid, decayed mass. In 

 these cells there were a few nuclei of normal size ; (a) the greater number, 

 however, were swollen in varying degrees, with one or two well stained nuc 

 leoli ; (b) the contents of the swollen nuclei, when freshly examined, werc^ 

 found to be homogeneous (see Fig. 6) ; but in Fig. 3. they appear granular, 

 which is due to the treatment of the section whfle ha'rdening was going- 'Onj 

 In (c) we see leucocytes ; at (d), tw-o bacteria. The swollen epithelial nuclei- 

 are also distinctly visible in the markedly changed middle epithelial layers of 

 Fig. 2 (c). 



The swelling might be caused by the simple coagulation of the protoplasm, 

 following death ; or there was a mucous or colloidal degeneration. The latter 

 was so much the more probable, as changed nuclei were found in the gelatinous. 



