Marks , employed for classifying the Schizomycetes . 1 09 
the examination of the products of action of the Schizomy- 
cetes. This would seem to explain why the Koch-Fltigge 
school has given us several special modes of staining : — e. g. 
Kiihne’s methylene-blue method, the Ziehl-Neelson carbol- 
fuchsin method, the Gram-Weigert, and Koch’s various 
ingenious methods of preparing, staining, and mounting 
Bacteria ; why the various developments of culture on solid 
media have come from Germany ; and why the characteristic 
forms, colours, and liquefying powers of the colonies of 
Schizomycetes have received so much attention at the hands 
of the Koch-Fliigge school 
The above way of looking at the history would also seem 
to explain some peculiarities of the Paris school. The per- 
fection to which they have carried the method of dilution- 
cultures, as exemplified by Miquel’s results at the Montsouris 
laboratories ; their recent triumph, the Chamberland filter ; 
the successful pursuit of anaerobic Bacteria at a time when 
such anomalous organisms were looked at with suspicion ; 
and last, but by no means least, their remarkable persistence 
and success in the employment of virus-material which they 
treat as if it contained Schizomycetes, although no one can 
demonstrate the presence of organisms in it — I refer of course 
to the hydrophobia-virus — reminds one of the methods of the 
chemist and physicist with their assumptions of atoms and 
molecules which no man has ever seen. 
Each of these two schools has imparted much information 
to the other, and, naturally, their mutual reactions tend to 
eliminate their differences as schools in some respects, and to 
emphasize them in others. I think, however, that, taken as a 
whole, each has its special peculiarities much on the lines 
sketched above. Each of the schools, moreover, has given 
evidence of its fertility in the branching out of more special 
little bands of workers, whose particular object is to apply 
the results of bacteriology in certain directions. The hygienic 
institutions of various countries may be cited as examples, 
and nothing better illustrates the truth of the preceding 
remarks than the persistent difference in methods of culture 
