288 BACTERIOLOGY. 



uals dead of the disease, ibut all that has been learned 

 from careful study of the secondary manifestations of 

 diphtheria tends to the opinion that they are in no way 

 dependent upon the immediate presence of bacteria, and 

 that the occasional appearance of diphtheria bacilli in 

 the internal organs is in all probability accidental, and 

 usually unimportant. 



By special methods of inoculation ' (the injection of 

 fluid cultures into the testicles of guinea-pigs) diphtheria 

 bacilli can he caused to appear in the omentum, but this 

 is purely an artificial manifestation of the disease and 

 one that is probably never encountered in the natural 

 course of events. Very rarely similar results follow 

 upon subcutaneous inoculation. 



If a very minute portion of either a solid or fluid 

 pure culture of this organism be introduced into the 

 subcutaneous tissues of a guinea-pig or kitten, death 

 of the animal ensues in from twenty-four hours to 

 five days. The usual changes are an extensive local 

 oedema with more or less hyperaemia and ecchymosis 

 at the site of inoculation ; swollen and reddened 

 lymphatic glands ; increased serous fluid in the perito- 

 neum, pleura, and pericardium ; enlarged and hemor- 

 rhagic supra-renal capsules ; occasionally slightly swollen 

 spleen; and sometimes fatty degeneration in the liver, 

 kidney, and myocardium. In guinea-pigs, especially, the 

 liver often shows numerous macroscopic dots and lines on 

 the surface and penetrating the substance of the organ. 

 They vary in size from a pin-point to a pin-head and 

 may be even larger. They are white and do not 

 project above the surface of the capsule. 



• Abbott and Ghriskey: A Contribution to the Pathology of Experimental 

 Diphtheria. Johns Hopkins Hospital Bulletin, No. 30, April, 1893. 



