296 MICRO-ORGANISMS AND DISEASE [chap. 



Bacillus diphtluricey — This acute infectious disease, to 

 which children and young individuals are particularly 

 prone, shows itself in most instances as a severe inflam- 

 mation and fibrinous infiltration of the mucous membrane 

 of the fauces and pharynx, or also the larynx and trachea, 

 leading to, and early in the disease consisting in, a necrosis 



Fig. ii8. — Film Specimen of the deeper Laver of the Diphtheritic 

 Membrane, showing numerous Leucocytes and the Diphtheria Bacilli. 



of the superficial part of the mucous membrane, and thereby 

 changing this into a tenacious, whitish pseudo-membrane, 

 the " diphtheritic membrane." In most cases only the 

 mucosa of the fauces (tonsils, palatine arches, velum palati 

 and uvula, upper part of pharynx) shows this change, i.e. 

 into whitish-grey " diphtheritic membranes '' ; in other 



' Part of the following account is copied from Klein's Etiology and 

 Pathology of Infectious Diseases in Stevenson and Murphy's Treatise 

 on Hygiene, vol. ii. 



