36 
NOTES ON THE COMMON PATHOGENIC 
Genus, Theileria. Bettencourt, Franca and Borges. 
Species, Theileria parva. 
Syn. Piroplasma parvum. Theiler, 1903. 
This genus contains as yet only one species, T. parva , 
the parasite of East Coast Fever, and is peculiar among the 
intracorpuscular parasites of bo vines in being non-inoculable 
by means of blood. Bettencourt placed the species B. mutans 
in this genus. As this parasite is inoculable in blood, it would 
appear better to place it elsewhere, although the morphology 
has not yet been shown to conform to Nuttall’s requirements 
for the genus Babesia. The devastation caused by this parasite 
in South Africa since the year 1902 is well known. In 
East Africa T. parva has been recognised in the Ukamba 
Province, notably in the Kikuyu and Uakamba countries, and 
in the Nyanza Province. It is also known to occur in the Seyedie 
Province, and elsewhere on the coast. The Sleeping Sickness 
Commission of the Boyal Society found it present in Uganda, 
and it is now believed to have a wide distribution around Lake 
Victoria. 
Morphology. The parasite as it occurs in the red blood 
corpuscles is usually in the shape of delicate rods rarely exceed- 
ing 2yu, in length, or rings of Ip, to l'5p in diameter ; oval and 
ovoid forms also occur. Koch was the first (1897) to notice 
the occurrence of peculiar forms in the lymphatic glands, spleen, 
and less numerously in other organs of animals suffering from 
this disease. These ‘ Plasma Kugeln,’ or ‘ Koch bodies ’ as they 
are now called, are met with either free or as intraleucocytic 
bodies, varying from 10^ to 14^ in diameter. The cytoplasm 
stains blue with Bomanowsky’s modification, and contains 
within it a variable number of purple staining granules. Two 
types of this body may be recognised ; that in which the 
granules are coarse and less numerous, and a second in which 
they are very fine and densely packed in the cytoplasm. In 
such of the latter forms as are mature and have been broken 
down in the preparation of the film it will be seen that each 
red or purple dot is associated with a delicate blue body. 
The individual picture is that of an extra- cellular Theileria. 
Nuttall, Fantham, and Porter have demonstrated that a multi- 
