THE STRUCTURE OF TRYPANOSOMA LEWISI. 7995 
The; Structure of Trypanosoma lewisi in 
Relation to Microscopical Technique. 
By 
E. A. Minchin, 
Professor of Protozoology in the University of London. 
With Plates 21, 22, and 23. 
INTRODUCTION. 
Mucu has been written of late years about the minute 
structure of trypanosomes, and also about the merits or 
demerits of the various methods in vogue for preparing them 
for examination with the microscope, that is to say, the 
technique of fixing, staining, and preserving these tiny 
creatures. Since our knowledge of the structure of trypano- 
somes is based almost entirely on the results of a number 
of complicated chemical and physical processes practised on 
a very delicate protoplasmic body, it is clear that a knowledge 
of the effects produced by these processes on the organisms 
are most important in interpreting the microscopic image 
finally obtained, in order to estimate, in any given case, how 
far the trypanosome may have undergone deformation or 
change as the result of the treatment it has gone through. 
In a perfect state of Scientific knowledge it would, no doubt, 
be possible to deduce exactly such results from the known 
action of the reagents employed upon the protoplasmic body, 
but in the present condition of our knowledge it is only 
possible to arrive empirically at an approximate estimate of 
the effects of technique by comparing carefully the results 
yielded by it. 
In order to eliminate as much as possible disturbing factors 
