PHOTOGRAPHIC INTRODUCTION 



As there are manuals dealing with photomicro- 

 graphy in its various branches already in exist- 

 ence, a complete description of the methods and 

 apparatus employed seems unnecessary, and it only 

 remains to state which of the usual methods were 

 selected, and what deviations from these methods 

 were made to meet the requirements of particular 

 cases. 



A horizontal camera was employed throughout 

 except in the few instances where the nature of the 

 specimen compelled the use of a vertical apparatus. 



The microscope stand invariably used was a Zeiss 

 No. IA. The arrangement for clearing the stage 

 which this stand possesses was found very con 

 venient when culture plates and similar objects were 

 to be photographed. 



Apochromatic objectives were always used : their 

 superior detinition and their inherent property of 

 photographing equally well in all colours of the 



