24 Comparative Studies 



such as edema and inflammation, even more so than when 

 inoculated alone. It also produced loss of appetite, 

 drowsiness, etc., in the animal inoculated. He inoculated 

 guinea pigs with diphtheria antitoxin, and subsequently 

 inoculated some with the pseudo-diphtheria bacilli and 

 others with the true diphtheria bacillus. Those inoculated 

 with diphtheria bacilli remained well, while those inocu- 

 lated with the pseudo-diphtheria bacilli showed the local 

 reactions observed after inoculations with these organisms. 

 He believes this to be a reliable method of differentiating 

 between the two organisms. 



C. Fraenkel (23), in the differentiation between the true 

 and pseudo-diphtheria bacilli, also experimented with 

 diphtheria antitoxin, free from antiseptic material, to 

 determine whether it could serve as a means to differentiate 

 between the Loffler bacillus and the pseudo-diphtheria 

 bacillus. He experimented with seven cultures of the 

 pseudo-diphtheria bacillus derived from the eyelids of 

 healthy persons, and from several cases of conjunctivitis 

 crouposa ; but the results were entirely negative. He then 

 repeated the experiments of Spronck, and obtained similar 

 results. Variable quantities of the cultures were injected 

 into the subcutaneous tissues of guinea pigs, in this manner 

 establishing the character of the cultures. In the second 

 series of experiments he also used antitoxin at the same 

 time. The results were as follows : Some of the cultures 

 he injected into animals, in quantities of 5 to 10 c. c., pro- 

 duced considerable disturbance at the point of injection in 

 the nature of swelling and infiltration, which after two 

 days, or at the most three days, entirely disappeared. In 

 no instance did he observe disturbances of general nature 

 reported by Spronck as, loss of appetite, weakness, loss of 

 weight, or change in temperature. Even in very large 

 doses, up to 50 c. c., the results were approximately the 

 same. There were no fatal results ; these results indicat- 

 ing that the antitoxin was without influence. The result 



