o64 RESEARCH IN PROTOZOOLOGY 



added to the leptospira medium. The protozoa were able to fer- 

 ment some, but not all of the sugars. A given species was definitely 

 characterized by the sugars it was able to utilize. Thus Her- 

 petomoiias elmassiani in cultures derived from the insect hosts 

 from North and South America and from the plant host from 

 North America was able to ferment thirteen sugars and other 

 carbohydrates with acid formation. These were glucose, levulose, 

 mannose, saccharose, raffinose, inulin, galactose, maltose, salicin, 

 zylose, mannitol, dextrin, and arabinose. It did not attack amyg- 

 dalin, lactose, dulcitol or rhamnose. On the other hand, Her- 

 petomonas lygceormn, although found at times in the same plant 

 and insect hosts, was able to ferment only glucose, levulose, and 

 mannose, and none of the other fourteen compounds. 



Another method of identification was established by means of 

 such cultures. Noguchi injected a rabbit on four occasions at 

 intervals of four days with one to two cubic centimeters of a 

 rich culture. On the ninth day after the last injection he secured 

 an immune serum. When 0.05 of one cubic centimeter of this was 

 added to one cubic centimeter of a culture of the same species of 

 flagellate the cells in the culture swelled and burst, thus caus- 

 ing clearing of the medium and the formation of a layer of 

 whitish sediment. The serum was efifective against all strains of 

 the species, even when derived from the alternate hosts. A 

 variety of other hemoflagellate species in culture were tested with 

 these immune sera, but no relationship was indicated between the 

 latex protozoa and other groups, although there was a slight 

 reaction of each of the two latex flagellate species tested to the 

 immune serum derived from the other one. 



These methods of species identification will prove valuable in 

 the future in the discovery of insect vectors of hemoflagellates, 

 since forms in insects can be definitely established as identical with 

 or different from strains found in infections under considera- 

 tion. 



Even with media in which the latex flagellates multiply, the iso- 

 lation of new strains from plants is difficult. Often the organisms 

 die without beginning to divide to form new individuals. The 

 transfer from a successful culture to new tubes of culture medium 

 is very uniformly successful, however. The sterilized medium de- 

 scribed below is suitable for subcultures from the blood culture 

 media. 



