PROTOZOA OF LATEX PLANTS 263 



The insect transmitters in other cases are unknown, but will 

 probably be found to be members of the insect family lyceid^, 

 to which all of the above species belong. The lyg.eid^ all feed 

 upon plants, and some of them have been known previously as 

 hosts of hemoflagellates. 



SPECIAL METHODS OF STUDY 



Recently devised methods have made it easy to identify and 

 work with the protozoa of latex plants. The following procedures 

 have to do with the maintenance of such forms under laboratory 

 conditions in cultures and in plant and insect hosts, as well as 

 with methods of staining and examining the organisms from these 

 sources. 



Cultivation of latex flagellates. Cultures of latex flagellates are 

 difficult to establish. Suitable media may be inoculated with the 

 organisms many times without the formation of successful colonies. 

 Yet when multiplication begins under these artificial conditions 

 divisions are rapid and great numbers of new individuals appear. 



Franchini (1923) and Nieschulz (1924a) used plates of Noller's 

 horse blood a§^ar in the cultivation of a flagellate from a plant 

 of Euphorbia cereifonnis which grew in the Botanical Gardens at 

 Bologna. Noller's medium is a nutrient agar, containing one per 

 cent of agar and one per cent of glucose, to which an equal part 

 of defibrinated horse blood is added before pouring plates. 



Migone (1922) in Paraguay used a human blood agar to cul- 

 tivate Herpetomonas bordasi (Franga) from the host plant Mor- 

 renia odorata. 



Noguchi (1926) in the United States succeeded after many at- 

 tempts in establishing seven strains of latex herpetomonads on 

 his leptospira medium which has the following composition : 



NOGUCHI'S LEPTOSPIRA MEDIUM 



0.9% sodium chloride 800 parts 



Fresh rabbit serum 100 parts 



2% nutrient agar 100 parts 



Rabbit hemoglobin 10 parts 



The rabbit hemoglobin is made by lakin^ one part of defibrinated blood 

 with three parts of distilled water. 



By the use of cultures Noguchi (1926a) devised two important 

 methods of identifying species of hemoflagellates. In cultures in 

 which the flagellates had become established, various sugars were 



