Annals of the Transvaal Museum. 
55 
with P. bigeminum of a pure infection ; the result was that they showed 
this parasite after the usual period of incubation. Thus the independence 
of marginal points to the cycle of P. bigeminum was demonstrated in the 
reverse order. Accordingly, no doubt can any longer be left that these 
peripheral bodies represent a genus of their own which produces a specific 
disease in cattle. 
I have proposed to give the name Anctplasma marginale to this 
parasite. This anaplasma is transmitted by ticks, and it is a noteworthy 
fact that the incubation time by tick transmission is much longer than 
that after inoculation of the animals with blood ; in the experiments 
carried out by me it varied from fifty-five to seventy-five days. Accordingly, 
we understand the results of experiments of the Americans, which were 
started in the summer. They exposed cattle to tick infection ; they 
noticed the appearance of P. bigeminum first, having a shorter incubation 
time, and only later in the year, after the long incubation time, they 
noticed the appearance of Anaplasma marginale. 
It has already been indicated that blood of an immune animal is 
infective ; such an animal forms the reservoir of the virus. This is a 
peculiarity of the piroplasma diseases, to which group anaplasmosis also 
belongs. It may be of interest to state my opinion that anaplasmosis is 
probably the disease which the farmer has hitherto called gall-sickness. 
Up to the present time we know of three different parasites in South 
Africa which are found in the blood of immune cattle — P. bigeminum , 
P. mutans , and Spirochaeta tlieileri— and to these will now be added 
anaplasma marginale ; they can all be transmitted by the inoculation of 
blood and by ticks. 
