PARASITIC PROTOZOA FOUND IX SOUTH AFRICA. 335 



pulp of the cabbage stalk, in company with eel-worms and an 

 Amoeba. No insects w^ere observed on the infected cabbages. 

 Some rounded post-Hagellate forms, unfortunately few in number, 

 were rubbed into another uninfected cabbage stalk, but without 

 cross-infection taking place. This herpetomonad, for purposes of 

 identification and reference, may be named Herpctoinonas 

 brassicfc. It is of interest to note that herpetomonads have 

 already been found in plants, for these flagellates were observed 

 in the latex of members of the Euphorbiaceaj in Mauritius in 

 1909. More recently they have been found in other orders of 

 plants. Sometimes insects, such as various plant bugs, are found 

 crawling over the infected plants. 



Elsewdiere in this Journal (see p. 344) I record the finding 

 of a Herpetomonas in water cultures of South African soils. It 

 measures Qja to 21jx in body length and I'opi to 3^ in breadth, and, 

 for purposes of reference, is named by me H. tcrricohc. The soil 

 herpetomonad possesses a kinetoplast (also known as a 

 kinetonucleus and as a blepharoplast), so differing from the inter- 

 esting allied organism, PwJeplomonas, fovmd by Woodcock"'-' 

 (1916) in sheep and goat dung in England. 



Herpetomonads are well known to occur naturally in tin- 

 alimentary tracts of insects and other invertebrates, also in the 

 guts of a few vertebrates and in the blood of a few vertebrat-^s. 

 We have thus presented within this one genus a varied dis- 

 tribution of habitat, ranging from free-living to parasitic, and 

 passing from life in moist soil to saprozoic existence in the 

 alimentary tracts of animals, and finally to parasitic life in verte- 

 brate blood and tissues, culminating in the pathogenic 

 leishmaniases. Herpetomonads are also parasitic in some plant- 

 tissues. 



That leishmaniases are insect-borne herpetomoniases is no 

 new opinion, and much experimental work has been done which 

 has pointed to this being a fact. Laveran and Franchini (1920) 

 have shown that certain herpetomonads from the latex of 

 Euphorbia nereifoUa produce flagellate infections when inoculated 

 into white mice.f In this connection, it is possible that plants 

 infected with herpetomonads, in districts where kala-azar is 

 endemic, may be concerned in the dissemination of this leish- 

 maniasis. I have held this opinion for many years, and in 1915 

 I drew attention to this possibility and stated t : " Nearly three 

 years ago I was informed by a competent authority that a 

 number of Euphorbia containing Herpetomonads grew outside a 

 certain hospital sitiuited in an area in which kala-azar was 

 endemic, and in which kala-azar patients were being treated. 

 The shrubs w^ere infested by insects. It seems remarkable that 

 no attempt was made to trace a possible connection between the 

 plant herpetomonad and kala-azar; doubtless such a possibility 



* Phil. Trans., B 207, pp. 376, 382. 383. 

 + IhiU. Sor. Path. Exot., xiii, pp. 796—800. 

 + Annals Trap. Med. and Parasitol, ix, p. 341. 



