PARASITIC PltOTOZOA FOUND IX SOUTH AFRICA. 333 



A very few Eni^oiiccha hovis Liebetanz were found in the. 

 reticulum of an ox killed in Johannesburg. The amoebae seen 

 measured 20n to 23^ in diameter, and one with an extended 

 lobose pseudopodium measured 3()[,i across to the free edge of the 

 pseudopodium. A cyst of this amtieba measured about 18ji in 

 diameter. 



Mastigophora. 



Most of the Flagellata previously recorded have been seen 

 again. Remarks are appended on herpetomonads. 



IIKUPETOMONAS IX VARIOUS HABITATS. 



A young white rat was inoculated intraperitoneally on 

 on February 20, 1922, with the intestinal contents of a house- 

 fly, Micsca domestica, infected with Herpetomonas musccc 

 domesticce. The blood of the rat was examined daily at about 

 11 a.m. This daily examination is absolutel}^ necessary, and the 

 omission of it accounts for discrepancies in the accounts of authors 

 who onlj? examine the experimental host's blood casually, every 

 few days, or — as one author recently expressed it — " at intervals 

 of a few days." In the case of my experimental rat, a few young 

 developing flagellate herpetomonads were seen in the ear blood 

 on the ninth day after inoculation. These herpetomonads, how- 

 ever, were only seen on second examination of ,the blood on the 

 ninth day, namely, in the afternoon, the blood appearing to be 

 negative in the morning. Possibly there was a slight infection of 

 the rat on the twenty-fifth day, but the infection was too slight 

 to confirm from stained preparations. However, on the thirty- 

 fifth day (March 29), there was a crop of flagellates in the blood 

 of the rat in the morning when the blood was examined at 

 11 a.m. In the afternoon of the same day at 3 p.m. the blood 

 was again examined, but no parasites were then seen. The 

 infection liad fulminated and then faded out, for the results of 

 subsequent daily examinations were negative. The rat was in 

 good health and not showing infection at the time of reading this 

 paper, 144 days after inoculation. (The rat has remained well 

 to the end of 1922, and has shown no further infection, having 

 thus lived 815 days after inoculation, during which there was 

 only one fulminating period followed by apparent recovery.) 



It is of interest and importance to note the source of the 

 Herpetnmonas muscce dorncsthcc used in this experiment, and to 

 draw attention to the difficulty of finding the herpetomonad of 

 the house-fly. Only four infections of Musca dotncstka* have 

 been observed by me in South Africa out of 286 house-flies 

 examined during the last two 3- ears. Also, in England I had 

 very great difficulty in finding this herpetomonad, as it did not 

 occur in flies found in houses. In Johannesbiu'g the infected 

 flies have only been found in a horse's stable, and only during 



* The house-flies were kindly identified for me by Mr G. A. H. Bedford, 

 Entomologist at the Veterinary Research Laboratories, Onderstopoort. 



