vi PREFACE 



Pfeiffer is the only work with which we are 

 acquainted which systematically illustrates by a 

 series of photographs the life history of a specific 

 micro-organism. Excellent as this work is, the cost 

 prevents it from being one of the ordinary working 

 books possessed by the student. The present work 

 has adopted the idea of the " Atlas " in that it pro- 

 vides a series of photographs of preparations of micro- 

 organisms and their cultures, such as are usually 

 met with, and made by, the student in an ordinary 

 course of practical Bacteriology. It is hoped on the 

 one hand, that it may be a laboratory handbook 

 to direct the attention of the student to the points 

 which he should observe in his own preparations, 

 at the same time helping the teacher by providing 

 a series of grouped illustrations ; whilst on the other 

 it is thought it may find a place in the library 

 of the medical officer of health and other prac- 

 titioners, as an atlas to which on certain occasions 

 he may find it convenient to refer. It is in no 

 sense a text-book of Bacteriology, and the letterpress 

 merely serves to link together and emphasise the 

 teachings of the photographs. The illustrations are 

 taken from fairly typical cultures and preparations, 

 and though the appearances vary so much with 

 varying conditions, it is hoped that those presented 



