PROTOZOA OF LATEX PLANTS 261 



for microorganisms and described accurately by DuPorte {Journal 

 of Parasitology, 11:183-194), who so carefully pictured them 

 that they can be identified beyond reasonable doubt. Bruni (1925) 

 also pictures cell nuclei as well as herpetomonads, confusing the 

 two. In Fig. 17 A, latex cell nuclei are shown in the presence of 

 herpetomonad flagellates. Thoroughly studied cases of herpetom- 

 onads of latex plants have frequently shown a few Lcishmania- 

 like forms. These have not yet been proven to have existed as 

 intracytoplasmic parasites in the usual sense of the term, but have 

 been found with the herpetomonads in the latex, insect intestinal 

 contents, or cultures. These Leishjiiuiiia-like forms may represent 

 small rounded herpetomonads rather than definite stages in the 

 life-history of the flagellates. Whenever accounts of latex protozoa 

 other than herpetomonads are presented extensive proofs should 

 be furnished for the claims as to the nature of the forms under 

 observation. 



It is probable that a very large number of species of true her- 

 petomonads exist in latex plants. Only six species have been 

 named, however. The species Herpetomonas davidl (Lafont) has 

 been the subject of extensive research. Euphorbia flagellates from 

 all parts of the world have been assigned to this species. It is 

 possible that in some cases the organisms observed belonged to 

 other closely related species. Herpetomonas ehnassiani (Migone) 

 and Herpetomonas lygceorum Noguchi were distinguished ac- 

 curately by Noguchi, whose work with these protozoa and some 

 insect flagellates and leishmanias established the possibility ot 

 identifying such organisms with other strains of the same species 

 even in cases derived from alternate hosts, and to distinguishing 

 them from other species even when morphologically similar. Her- 

 petomonas bordasi (Franga) has not been studied extensively, 

 but is well characterized by its original description. Herpetomonas 

 ficniim was described by Fantham in 1925, but has not been studied 

 by others. A flagellate has recently been reported from a fig 

 species by Bancroft in Queensland. Herpetomonas frangai was 

 described by Aragao in 1927 in a species of Maniot in Brazil. 



Insects zvhich serz'e as alternate hosts. All latex flagellates, so 

 far as known, are dependent upon insect hosts for transfer from 

 one plant to another. 



Herpetomonas davidi is reported as being transmitted by 

 Stenocephahis agilis in Portugal (Franga, 1920), by Dieuches 



