INFECTION AND INTOXICATION. 7 



indeed possible by using the bodies of susceptible guinea pigs 

 and rabbits to show that identical pathological changes can be 

 produced by inoculation with the toxalbumin alone. A closer 

 study of the lesions shows them to be different from those 

 caused by the pus-producing cocci. Such a lesion in the liver 

 of the guinea pig, resulting from diphtheria intoxication, is 

 shown in Fig. 2. Note here that a destruction of cells has 

 taken place, but that no bacteria are to be seen in the neighbor- 

 hood of the dead cells. The cells themselves present a different 

 appearance from those seen in the kidney abscess. Individu- 

 ally they are better preserved ; their outlines are sharper, and 

 they are more easily made out than the normal cells. Examined 

 in the fresh state, in physiological salt solution, they present a 

 characteristic glassy appearance, whence the term "hyaline," 

 which is often applied to them. That they are necrotic is 

 shown not only by the behavior of their protoplasm in the 

 presence of staining agents, but also by the absence of normal 

 nuclei in them. For the most part, the nuclei have entirely 

 disappeared, but here and there a shrunken one can be seen, 

 and occasionally small pigmented fragments are still preserved. 

 The intensity of the process evidently grows less as one pro- 

 ceeds from the center to the periphery of such a focus, and at 

 the extreme edge a variable number of leucocytes are encoun- 

 tered. They are never accumulated in quantities, such as are 

 seen in abscess formation, and such a lesion shows no tendency 

 to undergo softening with the production of an abscess or 

 cavity. 1 



With respect to the toxalbumins which are derived from the 

 higher plants (ricin, abrin), I have found that the pathological 

 lesions which they cause are similar, if not identical, with those 

 produced by the toxalbumins of bacterial origin. 



Besides the toxins of vegetable origin, toxic proteid sub- 

 stances, some of which are of great potency, are yielded by the 

 animal kingdom. Among these have already been mentioned 



1 When it is considered that these toxins are soluble substances, and pre- 

 sumably in perfect solution in the body fluids, the explanation of their tendency 

 to produce focal effects is not at once evident. Several hypotheses have been 

 advanced to account for this phenomenon. See "The Pathological Changes 

 Caused by Certain So-called Toxalbumins." Medical JVe-ws, Phila., Aug. 4, 1894. 



