802 THE LEISHMANIOSES 



Sergent) and in Greece (Cardamatis). The percentage infected is much greater 

 in the summer months than in winter. A cat was also found suffering from the 

 spontaneous disease in Algiers (Ed. and Et. Sergent, Lombard and Quilichini). ] 



3. Leishmania tropica. 



Syn. Leishmania furonculosa. Helcosoma tropicum. 



The endemic granulomata of warm countries (Oriental sore, Aleppo boil, 

 Delhi boil, and known also by innumerable other local names) are caused by 

 a protozoan organism, discovered by Wright (Helcosoma tropicum) and by 

 Marzinowsky and Bogrow, and belonging to the genus Leishmania. 



Appearance in the tissues. In the tissues the parasite is indistinguishable 

 from the parasite of kala azar : it occurs within the cells, generally in the 

 macrophages, endothelial cells and mononuclear leucocytes, but occasionally 

 in the polymorphonuclear leucocytes and in cells of the connective tissue. 



Appearance in culture. In cultures L. tropica is distinguished from L. 

 donovani by the early division of the flagellum (some cells have two flagella 

 at their anterior end) and by the greater length and more marked flexuosity 

 of the flagellum (Nicolle and Sicre). 



[Kow found the following differences between L. donovani and L. tropica 

 when the two parasites were grown on Nicolle 's medium at the same time. 



[1. The growth of L. tropica is much more luxuriant than that of L. donovani 

 over the same period. 2. L. tropica is distinctly larger than L. donovani. 

 3. The posterior extremity of L. donovani is distinctly more pointed than that 

 of any other. 4. There is a far larger number of fine vacuoles in the fully 

 formed flagellates of L. donovani than in L. tropica. 5. L. tropica is charac- 

 terized by the appearance of fine chromatin particles distributed in the body of 

 the parasites just as L. donovani is hollowed out by the presence of fine 

 vacuoles. These last two however may be purely accidental.] 



Experimental inoculation. The parasite of Oriental sore can be inoculated 

 into man and also into monkeys (Macacus sinicus) (Marzinowsky). 



[^Etiology. Leishmania tropica forms flagellates in bugs (Wenyon, Patton). 

 Patton has no doubt but that in Cambay the bug Cimex rotundatus is the only 

 transmitter of the disease in spite of the fact that his attempts to prove the 

 hypothesis experimentally have failed. Wenyon states that in Bagdad bugs 

 are not sufficiently numerous to account for the prevalence of the disease there 

 and concludes that the house fly is sometimes the transmitting agent but more 

 usually one of the mosquitoes or the sand fly Phlebotomus. ] 



[The disease encountered in South America and known as Espundia is due 

 to a parasite closely resembling L tropica but as there are certain differences 

 between the two organisms Laveran and Nattan-Larrier prefer at present to 

 regard the South American parasite as a variety of the latter L. tropica var. 

 americana. ] 



Other species of Leishmania. 



Three other species of Leishmania have been described as occurring in man 

 but the existence of these parasites and their identity are still matters of 

 doubt. One of them was described in Typhus fever by Lewaschew and by 

 Gotschlich [but see p. 847] : the second, in dengue by Graham : and the 

 third by Wilson and Chowning in the spotted fever of the Eocky Mountains, 

 a disease transmitted by a tick (Dermacentor occidentalis) ; Stiles and 

 Kicketts however have failed to confirm this last discovery. 



