316 
Piroplasmosis 
suggests that multiplication may occur within the infected corpuscles, 
some of which contain up to eight distinct parasites. If, however, multi¬ 
plication occurs within the corpuscles it must take place very slowly or 
we should have observed it in the living parasite. 
The results of our investigations forced me to the conclusion that 
the corpuscles merely serve as vehicles for the parasites wherein they 
are housed and maintained until they reach their destination within 
the tick, which serves as their vector. The seat of multiplication and 
invasion of corpuscles appeared to me to lie in the internal organs, 
a view which subsequently received support from the investigations of 
Meyer, who communicated the disease by the intraperitoneal transplan¬ 
tation of large pieces of infected spleen. 
Another striking feature connected with these parasites is the 
occurrence of “ Koch’s blue bodies ” in the internal organs and occasionally 
in the peripheral blood. These bodies (Fig. 11, is-is) were first observed 
by Koch and to-day are considered to be of prime diagnostic importance. 
They are termed “blue” because of their appearance in blood-films 
stained by any of the modifications of the Romanowsky method. When 
examined stained they usually appear rounded, the blue-staining proto¬ 
plasm containing discrete chromatin masses in varying numbers; at 
times they are seen to be breaking up, each mass of chromatin being 
accompanied or surrounded by blue-staining protoplasm. These bodies, 
which were regarded as developmental forms by Koch, have been 
made the subject of detailed study by Gonder, who states that he has 
seen them break up into their elements and scatter. They are encount¬ 
ered in the internal organs (lymphatic glands, spleen, etc.) before they 
appear in the corpuscles of the peripheral circulation. In some cases of 
East Coast fever the parasites do not appear in the corpuscles, whilst 
Koch’s bodies are found only in the internal organs. The bodies are 
found either free in the plasma or in cells—chiefly in lymphocytes— 
exceptionally in leucocytes. According to Gonder, these bodies (which 
he terms “agamonts”) undergo multiplication by schizogony, and I am 
inclined to agree with him. Accorditig to this view the parasites are 
first uninuclear, they grow, and the nucleus divides repeatedly until 
many small nuclei are formed, after which the minute parasites separate 
and scatter. It is presumably these small parasites which invade the 
corpuscles. The rest of the cycle of development, as outlined by Gonder, 
is so purely conjectural that we can afford to ignore it for the present. 
It is reasonable to assume, from what I have previously stated, that 
some of the intracorpuscular parasites represent sexual forms destined 
