PARASn'IC PROTOZOA FOUND IN S. AFRICA. 167 



division into four have been seen. The final stages of schizogony 

 have not been observed with certainty. Apparently the only ecto- 

 parasite known to occur on Burchell's coucal belongs to the Mallo- 

 phaga, and is said to be a new species of Degeeriella. A smear 

 preparation, stated to be of this bird-louse, has been found to contain 

 in the gut curious structures like partly digested avian red blood 

 corpuscles and peculiar sporozoitedike bodies. However, it is 

 generally considered that Mallophaga do not suck blood, and 

 definite conclusions regarding the transmission of the Leucocy- 

 tozoon are not permissible on the material available. I pro- 

 pose a new specific name centropi for this parasite, and so desig- 

 nate it Leucocytozoon centropi, with the specific characters stated 

 in the foregoing. The bird was also infected with Halteridium, 

 but that parasite is not likely to be spread by lice, as Halteridia 

 are usually transmitted by flies. 



Piroplasma caballi has been seen in the blood of a mule in the 

 Transvaal. 



Sarcocystis tenella. The work on the seasonal periodicity of 

 Sarcosporidia (S. tenella) in sheep has been continued. Unfortun 

 ately, fewer animals were availa^e than last year, and I was not 

 able to make observations during December, 1920, to March, 1921, 

 owing to absence in England. However, my results, taken weekly 

 as far as possible on fresh post-mortem material, show that in 1921 

 the spores of Sarcocystis tenella were very few in number or in 

 some cases absent in the heart-muscle (apex of the ventricle) of 

 sheep in the Pretoria district in the cold months of June, July and 

 August, but — extending my observations to the date of publication 

 of this paper at the end of 1921 — show an increase in numbers in 

 September and in December. It should be noted that in Johannes- 

 burg no rain was officially recorded during the three winter months 

 mentioned, showing that the season was slightly drier than in 1919 

 and in 1920, and the average temperature during that period was 

 lower than in 1919 or 1920. It is also of interest to mention that, 

 in mid-summer, young Miescher's tubes may be found in scrapings 

 of fresh heart-muscle after massage of the organ. 



Sarcosporidia have also been seen in the heart-muscle of cattle, 

 the species being Sarcocystis blanchardi, while S. moulei was seen 

 in the heart of goats, S. bertrami in the heart-muscle of horses and 

 S. miescheriana in that of pigs in the Transvaal. 



In the heart-smears of a reedbuck, Eediinca (Cervicapra) 

 arundinum, shot by Dr. Hertig in Barotseland, I have found 

 spores of a Sarcocystis. 



Infusoria. 



All the Ciliata previously recorded by me have been seen 

 again. In addition, periodicity has been studied in Cycloposthium, 

 and a few other ciliates have been observed in domestic animals 

 in South Africa for the first time. These results may now be 

 stated. 



Cycloposthium bipalmatam Fiorentini has been observed in 

 two horses in some detail over a period of four months, and general 



