TRYPANOSOMES, TRYPANOSOMIASIS, AND SLEEPING SICKNESS 89 
The kidneys were normal in most cases, sometimes they showed parenchymatous 
degeneration. 
The liver cells were often wasted, sometimes showing fatty degeneration, 
and had no nucleus or only a faintly stained one. Blood pigment was often to be 
found in the liver. 
The other organs showed nothing abnormal, except congestion of vessels. 
Surra, Nag an a, Etc. 
We examined microscopically the organs of rabbits, guinea-pigs, and rats 
infected with T. brucei and T. evansi, and the organs of young dogs infected with 
T. equip erdum. 
In the organs of animals infected with T. brucei we found in the brain and spinal 
cord congestion and a few haemorrhages around the vessels, as for the other organs, 
we can only confirm Baldwin's findings. We could not find a periodical variation of 
the pigment of the spleen, but the amount of pigment increased with the duration 
of the infection. In acute cases there were very often haemorrhages in the spleen 
destroying its tissue, and often extending up to the capsule. The liver showed 
small necrotic areas in places. 1 The lesions in Surra and Mai de Caderas 
were of the same nature, but showed slight variations. The amount of pigment in 
the spleen in these two latter diseases was always very small. Trypanosomas in 
groups were found in nearly all vessels. 
The organs of one pup infected with Dourine were normal, as were the brain and 
spinal cord. The spleen was not much enlarged, and was of normal microscopical 
appearance. The lymph glands were greatly enlarged, however, the enlargement 
being due entirely to the new formation of lymphoid tissue. 
Summary 
The pathological histological changes of the brain and spinal cord in cases of 
sleeping sickness were first described by Mott, Warrington, and the Portuguese 
Commission. Low and Mott describe the case of a European. Mott has recently, 
in a lecture on the cerebro-spinal fluid, recorded the changes found in some more 
recent cases. 
The changes described by all the authors are the small-celled infiltrations around 
the vessels of brain and spinal cord, especially remarkable through the presence of 
plasma cells. Some of the authors, especially Mo i t, have described diplococci as 
being present in the vessels of the central nervous system. In our three cases of 
sleeping sickness a few cocci and bacilli, negative to Gram, were seen in the brain, 
cord, and organs,, but they were so few in number that they could be considered as due 
1. This observation is. confirmed by Neporogny anil Yakimoff. Modifications du foie dans les Trypanosomiases experi- 
mentales (Recucil des Tr.ivaux dedies a M.- Lukianoff a l'occasion de son-jubile scientifique. St. Petersbourg, -190+). 
M 
