EXPERIMENTAL INOCULATION. 28 1 



to death within eight days, the organisms becoming generalised 

 and producing numerous minute nodules, especially in the spleen, 

 lungs, and liver. In the guinea-pig the disease is less acute, 

 though secondary nodules in internal organs are usually present 

 in considerable numbers. At the site of inoculation an inflam- 

 matory swelling forms, which soon softens and breaks down, 

 leading to the formation of an irregular crateriform ulcer with 

 indurated margins. The lymphatic vessels become infiltrated, 

 and the corresponding lymphatic glands become enlarged to the 

 size of peas or small nuts, softened, and semi-purulent. The 

 animal sometimes dies in two or three weeks, sometimes not for 

 several weeks. Secondary nodules, in varying numbers in dif- 

 ferent cases, may be present in the spleen, lungs, bones, nasal 

 mucous membrane, testicles, ovaries, etc. ; in some cases a few 

 nodules are found in the spleen alone. Intraperitoneal injection 

 in the male guinea-pig is followed, as pointed out by Straus, by 

 a very rapid and semi-purulent affection of the tunica vaginalis, 

 shown during life by great swelling and redness, of the testicles, 

 which changes may be noticeable in two or three days. By this 

 method there occur also numerous small nodules on the surface 

 of the peritoneum. Rabbits are less susceptible than guinea- 

 pigs, and the effect of subcutaneous inoculation is somewhat 

 uncertain. Accidental inoculation of the human subject with 

 pure cultures of the bacillus has in more than one instance been 

 followed by the acute form of the disease and a fatal result. 



Mayer has found that when the glanders bacillus is injected along with 

 melted butter into the peritoneum of a guinea-pig, it shows filamentous, 

 branching, and club-shaped forms ; in other words, it presents the characters 

 of a streptothrix. Lubarsch, on the other hand, in a comparative study of the 

 results of inoculation with acid-fast and other bacilli, found none of the above 

 characters in the case of the glanders bacillus (cf. " Tubercle "). 



Action on the Tissues. — From the above facts it will be seen 

 that in many respects glanders presents an analogy to tubercle 

 as regards the general characters of the lesions and the mode 

 of spread. When the tissue changes in the two diseases are 

 compared, certain differences are found. The glanders bacillus 

 causes a more rapid and more marked inflammatory reaction. 

 There is more leucocytic infiltration and less proliferative change 

 which might lead to the formation of epithelioid cells. Thus the 

 centre of an early glanders nodule shows a dense aggregation of 



