viii PREFACE. 



As then, so also now I hold that the comma-bacilli of 

 Koch do not fulfil the conditions which the cholera microbe 

 ought to fulfil. As then, so also now I agree with the pre- 

 vailing opinion that the comma-bacilli of Koch are an 

 important diagnostic guide. 



I have been credited by various writers with the contrary 

 statement; I have in the articles, as they first appeared, 

 tried to correct such statements, though without effect, and 

 I must therefore again state, that I fully agree with Koch 

 and others as to the constant presence of the comma-bacilli 

 in the cholera intestine and cholera discharges during the 

 early stages, but that here our agreement ends. That the 

 comma-bacilli of Koch are not accepted as the proved 

 cause of cholera, in this I am not alone, as, for instance, 

 Professor Baumgarten seems to think ; von Pettenkofer, 

 acknowledged to be the greatest living authority on the 

 etiology of cholera, holds this view, viz. that the comma- 

 bacilli are not the proved cause of cholera; Dr. D. D. 

 Cunningham of Calcutta, who during many years had 

 exceptional opportunities of studying this disease, is of 

 the same opinion. The English Cholera Commission 

 (Professor Roy, Dr. Sherrington and Dr. Brown); Dr. 

 Shakespeare of Philadelphia, and Dr. v. Emmerich of 

 Munich, are the most noteworthy observers who have arrived 

 at the same conclusion after special study of cholera. 



E. KLEIN. 



