MASTIGOPHORA 



397 



very closely except in its pathogenic properties. Cultures on 

 blood-agar have been obtained by Nicolle and are easily propa^ 

 gated at 22 C. Dogs and monkeys are susceptible to inoculation 

 and the human disease is probably contracted from dogs through 

 the agency of insects. The disease is relatively benign and recov- 

 ery is followed by prolonged immunity. Inoculation has been 

 practised in man in order to produce immunity. 



FIG. 166. Lciskmania Iropica, 

 forms observed in cultures. (From 

 Dofiein after Nicolle.) 



FIG. 167. Try pano plasma cy- 

 prini. Bl, Blepharoplast; N, nu- 

 cleus. X 2000. (After Doflein.} 



Leishmania Infantum. Nicolle in 1908 observed this organ- 

 ism in the spleen, liver and bone marrow of children dying from 

 splenomegaly in northern Africa. The disease resembles Kala- 

 Azar in all respects except that the patients are all very young. 

 Dogs are naturally infected with this parasite and are probably 

 the source of the human disease. Cultures on blood-agar are 

 readily obtained and kept up indefinitely without special difficulty. 



