1905.] Sleeping Sickness and Trypanosomiasis, etc. 



235 



showed a high congestion of the vessels of the brain and spinal cord, with 

 haemorrhages, around the vessel walls, containing lymphocytes, a few 

 leucocytes, and phagocytes. The intima showed large proliferated endo- 

 thelial cells, the vessels often contained very many leucocytes. Numerous 

 haemorrhages in the grey substance of the spinal cord were frequently seen. 

 Some of the dogs, rabbits, and guinea-pigs showed the changes in the spinal 

 cord, and to a less extent in the brain. The ganglion cells exhibited similar 

 alteration as in the human cases. In some of the animals no chancres 



O 



around the vessels and very little alteration of the ganglion cells and fibres 

 were noted. 



Many of the lymph glands presented the picture of haemo-lymph glands 

 with a few pigment granules; sometimes an irregular patchy appearance was 

 seen, the centre consisting of a light stained area with numerous red cells 

 and phagocytes, the periphery of normal lymph tissue with a small number 

 of follicles. The spleen showed congestion in the more acute cases, with 

 irregular hyperplasia of the malpighian bodies, in the older cases hyperplasia 

 of the connective tissue. Tor comparison the brains, cords, and organs 

 of animals infected with T. dimorphum (Gambian horse disease) were examined. 

 In a few cases the same haemorrhages as described above and localised in the 

 grey substance of the nervous centres were seen. The lymph glands showed 

 the peculiar appearance ; as noted above the light spaces were completely 

 filled with blood pigment. The spleen showed hardly any pigment. 

 Trypanosomes were found mostly clumped together in the vessels of the 

 different organs of all animals dying with numerous parasites in the peripheral 

 blood. 



Conclusions. 



(1) In the cases of Sleeping Sickness there is a pronounced congestion of 

 the blood vessels of the central nervous system together with a small celled 

 infiltration around the vessels of the brain and spinal cord, especially in the 

 grey substance. 



(2) Chromatolysis and pyknosis of the ganglion cells of brain and spinal 

 cord. 



(3) Inflammation of the leptomeninges of the brain and spinal cord. 



(4) Neuritis of the peripheral nerves. 



(5) The more chronic the case and the more pronounced the symptoms 

 the greater the changes in the brain and cord. 



(6) The majority of the lymph glands exhibit the picture of haemo-lymph 

 glands. 



(7) Small necroses of the spleen and signs of degeneration of the bone 

 marrow. 



vol. lxxvii. — B. s 



