398 BACTERIOLOGY. 



inoculation, as well as of the liver, spleen, kidneys, 

 lymphatic glands, and elsewhere, reveals the presence 

 of localized foci of cell-death, characterized by a pecu- 

 liar fragmentation of the nuclei of the cells of these 

 parts. 



This destruction of nuclei results in the formation 

 of groups of irregularly shaped, deeply staining bodies, 

 having at times the appearance of particles of dust, 

 while again they may be much larger. Some of them 

 are tolerably regular in outline, while others are irregu- 

 larly crescentic, dumb-bell, flask-shape, whetstone- 

 shape, or bladder-like in form. Occasionally nuclei 

 having the appearance of being pinched or drawn out 

 can be seen. At some points the fragments are grouped 

 in isolated masses, indicating the location of the 

 nucleus from the destruction of which they originated. 

 These particles always stain much more intensely than 

 do the normal nuclei of the part.' Oertel showed long 

 ago that these peculiar alterations in their distribution 

 are characteristic of human diphtheria, and the demon- 

 stration of similar changes in animals inoculated with 

 this organism is important additional proof that diph- 

 theria is caused by it. 



By the inoculation of certain animals an affec- 

 tion may be produced in all respects identical with 

 diphtheria as it exists in man. If one open the 

 trachea of a kitten and rub upon the mucous mem- 

 brane a small portion of a pure culture of this organ- 

 ism, the death of the animal usually ensues in from two 



iSco "The Histological Changes in Experimental Diphtheria," also 

 "The Histological Lesions Produced by the Toxalbumin of Diph- 

 theria," by Welch and Flexner, Johns Hopkins Hospital Bulletin, 

 August, 1891, and March, 1892. 



