2o THOMPSON YATES AND JOHNSTON LABORATORIES REPORT 
or in the blood and exudates of infected animals. Plimmer claims that the parasite 
of ' Gambia Fever ' differs from the sleeping sickness trypanosoma : the former 
being longer, generally larger, and more easily stained than the stumpy, larger- 
vacuoled, badly-staining trypanosoma of sleeping sickness. After the examination of 
many animals infected with the various strains of T. gambiense the distinctions which 
Plimmer notes appear to be artificial. Both long and short, large and small forms 
are seen in their blood ; on comparing these with the parasite in the blood of a native the 
same forms are seen. No differences have been noticed in the staining reactions. 
The parasites in serous blood require longer staining than do those in less anaemic 
blood. 
Comparisons were made by injecting animals both with a sleeping sickness and a 
' Gambian Fever ' strain. It was impossible to detect any difference whatsoever either 
in the control films or films made from the animal. Animals were injected with blood 
containing a majority of short stumpy-formed parasites, these animals have shown as 
many or more longer forms than stumpy ones in their blood. Careful measurements 
have not shown any difference between the sleeping sickness or 'Gambian Fever' or 
any other ' Trypanosome Fever ' parasite. These comparison slides were made from 
the same species of animal, and, with two exceptions, the number of passages of the 
parasite was the same. Chromatic granulation is common both to the long and short 
forms. Parasites appear to possess these granules more often if the infected animal 
is dying or if large numbers of parasites are present in the blood. They have also 
been prominent in the trypanosomes undergoing degeneration in the blood of an 
animal treated with arsenic or trypanroth. In some cases they have almost filled up 
the whole body of the trypanosome, making it difficult to distinguish the micronucleus 
and interfering with the macronucleus. These granules may form in clusters or may 
be ranged in comparatively regular rows, they may vary from a pin-point to a 
size equal to or larger than the macronucleus in size. Trypanosomes containing such 
granules may be run through several passages and still possess granules. One mouse, 
Experiment 692, had enormous numbers of trypanosomes containing these granules ; 
all the subinoculated animals became quickly infected, and though this strain was run 
through eleven passages the parasites still contained the granulations. The granules 
were present in both single and divisional forms of the micro-organism. These 
granules were present in the trypanosomes of the subinoculated animals — rabbits, rats, 
mice, and pup. In a monkey a less number of granules were seen. The twelfth 
passage into a guinea-pig infected the animal, but the trypanosomes had almost lost 
the granules. In the blood of this animal granular trypanosomes were noted from 
time to time ; it died from broncho-pneumonia ; its subinoculated rats have never 
shown granular forms of the parasite. 
