178 AIDS TO BACTERIOLOGY 



Trypanosoma equiperdum is found in dourine (mal 

 du coit) in horses, and is transmitted by coitus. 



Somewhat similar organisms are frequently found in 

 the sewer-rat (T. Lewisi), apparently doing little or no 

 harm, and in many other mammals, birds, reptiles, and 

 fishes. T. Lewisi is conveyed by a rat-flea. Noller 

 and also Wenyon say that it is not the act of biting which 

 infects the rat, but that infection is brought about by the 

 rat licking up the faeces passed by the flea while feeding. 



The trypanosomes stain well by Leishman's method. 

 By cultivating on a blood agar (ordinary agar, with an 

 equal quantity of sterile defibrinated rabbit's blood) many 

 of the trypanosomes may be grown T. Lewisi with ease, 

 T. Brucei with more difficulty. 



Leishmania Donovani. The spleen and liver of persons 

 suffering from kala-azar (tropical febrile splenomegaly, 

 dumdum fever) contain Leishman-Donovan bodies. They 

 are round or oval bodies, measuring 2-5^ to 3'5/^. Some 

 sort of cuticle is apparently present, and there are two 

 chromatin masses a large one, staining pale red with 

 Leishman's stain, and forming part of the periphery of the 

 parasite; and the other a small one, staining deep red 

 with Leishman's stain, situate opposite the other, in the 

 short axis of the parasite. Donovan suspected a reduviid 

 bug (Conorhinus rubrofasciatus, de Geer) as being a 

 possible transmitter of the disease. Patton has de- 

 scribed the complete development of the parasite in 

 Indian and European bed-bugs. A parasite indistin- 

 guishable from Leishmania Donovani was found by Nicolle 

 in the splenic smears of Tunisian dogs, but Donovan 

 failed to find it in an enormous number of smears from 

 Madras dogs. Nicolle' s parasite is considered to be a 

 separate species and is called Leishmania infantum. 



A goitre affection occurring in Brazil is said to be a 

 trypanosome infection. Donovan tritely remarks that 

 there appears ' to be no limit to the existence of the 

 parasitic flagellates in animal organisms, but what is 

 more astonishing and subversive of previously held views 

 is the occurrence of these parasites in the latex or milky 

 juice of plants.' Lafont found Herpetomonas (Lepto- 

 monas) in the latex of Euphorbia pilulifera in Mauritius, 

 and Donovan discovered these flagellates small, narrow 

 forms in the latex of the same plants growing in Madras. 



