816 THE FLAGELLATA 



6. Trypanosoma theileri. 



Trypanosome of " Galziekte." 



Cattle in the Transvaal [and in the Orange River Colony, Cape Colony and 

 possibly in other parts of South Africa] are subject to a disease, known to 

 the farmers of South Africa as Galziekte [gall-sickness], which is characterized 

 by anaemia and may or may not be accompanied by fever. It may assume 

 a malignant form and rapidly terminate in the death of the animal. Theiler 

 found a trypanosome in the blood of the affected animals and this was 

 described [almost simultaneously] by Laveran [and Bruce]. The trypano- 

 some of Galziekte ( T. theileri) is the largest of the mammalian trypanosomes, 

 being almost twice the size of T. brucei : it measures 60-70/x long by 3-4/w. 

 broad in the larger forms, while the smallest forms measure from 25-30/x 

 long by 2-3/A broad. The protoplasm stains deeply and is very granular : 

 the nucleus is oval and centrally situated : the centrosome is rounded, stains 

 well and is placed some little distance from the posterior end of the parasite. 

 Multiplication takes place by binary longitudinal fission. 



Cattle are the only animals susceptible to inoculation with T. theileri. 

 Cattle which survive an attack of the disease are immune. 



The disease is transmitted by the bites of flies of the family Hippoboscidce 

 (H. rufipes and H. macitlata). [H. maculata is very rare in South Africa 

 where it appears to have been introduced at the time of the Boer War with 

 cavalry horses coming from India (Laveran).] Theiler has succeeded in 

 infecting healthy animals by placing on them Hippoboscce taken from affected 

 animals. 



7. The trypanosomes of sleeping sickness. 



[Human Trypanosomiasis. Negro Lethargy. Trypanosome fever.] 



A. Trypanosoma gambiense. 



In 1898 Nepveu found trypanosomes in the blood of a man in Algeria, but 

 his descriptions were so lacking in precision as to make his conclusions 

 doubtful. 



In 1902 Dutton [in conjunction with Forde] discovered trypanosomes in 

 the blood of an European who had lived in Gambia for 6 years and who was 

 suffering from a disease which ultimately proved fatal. The disease was 

 characterized chiefly by an irregular fever which did not yield to quinine, 

 oedema of the face and lower limbs, cutaneous erythema, hypertrophy of 

 the spleen, enlargement of the lymphatic glands and general weakness. 

 Dutton described the parasite as Trypanosoma gambiense. 



Manson and Daniels, and Manson and Broden soon afterwards confirmed 

 Dutton's discovery by finding trypanosomes in man on the Congo, and cases 

 of human trypanosome fever were soon afterwards recorded by Baker in 

 Uganda, Brumpt in the Congo, and Forde in Uganda ; and Dutton and Todd 

 several times found trypanosomes in natives of Gambia suffering from mild 

 indefinite maladies. 



In 1903 Castellani found trypanosomes in the cerebro-spinal fluid of 70 

 per cent, of persons affected with sleeping sickness. The observations were 

 soon confirmed by Bruce and Nabarro and by Brumpt. Castellani's trypano- 

 some (Trypanosoma ugandense] is practically always found in the cerebro- 

 spinal fluid [as well as in the blood and gland juice (Nabarro)] of persons 

 suffering from sleeping sickness, and has never been found in the cerebro- 

 spinal fluid of persons free from the disease. 



Sleeping sickness is the cause of a very considerable mortality among the negroes 

 of the West Coast and centre of Africa : for some years past it has decimated the 

 negro population of Uganda and the Great Lakes. The disease has a great pre- 



