400 FAMILY: TRYPANOSOMID^ 



even yi^^, the serum of the animals inoculated with L. donovani agglut- 

 inated this organism and L. infantum, but not the two others. Similarly, 

 the serum from an animal inoculated with L. tropica agglutinated this 

 organism alone, and the same was true of the serum of an animal inocu- 

 lated with L. brasiliensis. From these reactions it appears that sero- 

 logically the organisms tested fall into three groups, in conformity with 

 the clinical types of disease produced. If the sera were added to the 

 culture media, they were similarly specific in changing the character of 

 the growth of the homologous organisms. 



LEISHMANIA IN MAN. 

 The Parasite of Kala Azar. 



Leishmania donovani (Laveran and Mesnil, 1903). — This organism, 

 which is often referred to as the Leishman-Donovan body, is a rounded, 

 non-flagellate stage of a flagellate which infects the vascular endothelium 

 and wandering macrophages of human beings, and produces the disease 

 known as kala azar. 



DISTRIBUTION. — Kala azar occurs in India, in Madras and in the 

 district north of the Bay of Bengal, in Calcutta and along the Ganges 

 and Brahmaputra, in Bengal and Assam. Cunningham and Pundit 

 (1925) have recently discovered the disease in the extreme South of 

 India opposite Ceylon. In China it occurs north of the Yang-tse in 

 a district between the coast and a line joining Pekin and Hankow. It 

 has also been recorded from Sumatra by Smits (1916), but from informa- 

 tion the writer has received there appears to be considerable doubt 

 regarding this observation. In Southern Russia it is found both west 

 and east of the Caspian Sea, in Transcaucasia and Turkestan, while Kiilz 

 (1916) has found it to be endemic in Mesopotamia. The whole of the 

 Mediterranean littoral and many of the islands are homes of the disease, 

 as also an area on the Blue Nile west of Abyssinia extending as far as 

 Khartoum in the north and towards Kodok in the south. The writer has 

 received information that the disease has been discovered in Kenya Colony. 



A case in a child has been recorded by Bouilliez (1916) near Lake 

 Chad, and another by Tournier (1920) in the Gaboon, both in West Africa. 



SYMPTOMOLOGY. — The disease occurs most usually in children or 

 young adults, and is due to invasion of the endothelial cells of the capil- 

 laries by the parasites, which are mostly concentrated in the spleen, bone 

 marrow, and liver, though the lymphatic glands, or, indeed, any organ, 

 may be found infected. The symptoms produced are chiefly enlargement 

 of the spleen and liver, progressive emaciation, anaemia, and an irregular 

 type of fever. Other symptoms may occur, such as enlargement of the 



