BLOOD-INHABITING FLAGELLATES IN GENERAL 247 



The herpetomonads found in the intestines of muscoid flies and 

 of fleas are readily available. H. muscce-domesticcu (H. miiscarum) 

 has been found in various species of Musca, Phormia, Lucilia, 

 Calliphora, CochUomyia, and Sarcophaga. H. ctenocepJiali has 

 been found in the fleas of the dog and the cat, Ctcnocephalus canis, 

 and C. fclis, respectively. These forms may be cultivated on N. N. 

 N. medium though it is difficult to start the culture because of 

 the bacterial contamination in the intestinal contents, particularly 

 of the flies. The adult fleas which feed exclusively on blood have 

 the habit of defecating as they near the end of a blood meal, and 

 it is frequently possible to catch the dejecta upon a sterile cover- 

 slip, and from this to transfer the organisms with a platinum loop 

 to a tube of medium. The flies should be washed in a bactericidal 

 fluid, and then immersed in sterile saline. Dissection should be 

 made with sterile instruments. The intestine is carefully removed 

 and is punctured near the esophageal end, care being taken not to 

 enter the space within the peritrophic membrane. The fluid which 

 exudes from the puncture will, on some occasions at least, be found 

 to contain herpetomonads free from bacteria, and from this fluid 

 cultures may be started on N. N. N. medium (Wenyon, 1926). 



Leishmaniasis of any kind is not indigenous to the United States, 

 and it is rare to find any cases. The few reported have been found 

 for the most part in immigrants or sailors. Consequently most of 

 the work done with Leishmania organisms has utilized cultural 

 forms. All species seem to grow readily on N. N. N. medium or on 

 Noguchi's serum medium (1924) which was devised for the 

 cultivation of spirochetes (see Chap. XXIX, p. xxx). Strains of 

 L. tropica, L. bra/:il{ensis, and L. donovaui are available in a num- 

 ber of laboratories in the country. 



