222 MICKOBES, FEEMENTS, AND MOULDS. 



We do not think that the dual nature of human 

 diphtheria, indicated by the researches of Klebs and 

 Loffler, is yet established. The symptoms, and still 

 more the histological lesions of this disease, are in 

 favour of its unity, and it may be owing to other 

 causes that the disease is more or less severe. 



The well-known polymorphism of microbes leads 

 us to think that the bacilli represent the adult form, 

 and the micrococci, or Microsporon, the early form of 

 a single species, which is in all cases the cause of 

 diphtheria and of its several manifestations — croup, 

 diphtheria, etc. Further researches are necessary to 

 decide this question. 



Whooping-cough and Influenza. — Burger has 

 lately discovered rods in the form of an 8 in the 

 sputum of whooping-cough ; they are found in great 

 numbers in the white scum, and are even visible to 

 the naked eye, and, like many other bacteria, they 

 can be stained by methyl violet. To this microbe 

 whooping-cough and its relapses are due, and it is 

 always present. It has not yet been cultivated. 



Influenza resembles whooping-cough in the course 

 it takes, and is probably also caused by microbes. 

 Letzerich has found micrococci in the blood, to which 

 he ascribes this disease, but his researches must be 

 repeated with greater care. 



Certain facts observed in medical practice have 

 led to the surmise that whooping-cough ifiay be re- 

 garded as an attenuated form of croup, just as vaccinia 



