42 THOMPSON YATES AND JOHNSTON LABORATORIES REPORT 
The Occurrence of the Parasites in Tissues and Fluids 
after Death 
Our examination of film preparations of tissues and fluids taken at autopsies are 
not completed, but it is interesting to note here the frequency with which the parasites 
have been seen in the pericardial, pleural, and peritoneal fluids when examined fresh. 
In three cases (62, see chart, 64, 76) parasites were seen, without centrifugalizing, in 
the pericardial or peritoneal fluid ; one-and-a-half, two, two-and-a-half hours, 
respectively, after death. In two of these cases numerous longitudinal divisional forms 
were seen in the pericardial fluid. In three other cases actively motile trypanosomes 
were seen in the pericardial fluid after centrifugalizing, fourteen, fifteen-and-a-half, 
twenty-and-a-half hours after death. In all these cases parasites were seen either the 
day before or a few days previous to death. In only one case has a trypanosome been 
seen in fluid from a lymphatic gland (omental) ; but in this case parasites were easily 
detected in the blood, post-mortem, and were very numerous in the pericardial and 
peritoneal fluids. 
Occurrence of Parasites in the Cerebro-Spinal Fluid 
During the stay of the expedition at Leopoldville, lumbar puncture was performed 
on forty-nine natives coming from many parts of the Upper and Lower Congo. Of 
these thirty-eight were proved to be suffering from trypanosomiasis, the parasites being 
found in the blood. In the remaining eleven cases no trypanosomes were seen in either 
the blood or cerebro-spinal fluid, and in some of them a diagnosis of some other 
disease, e.g., tubercle, dysentery, etc., was established either during life or -post-mortem. 
In twenty-five of the thirty-eight trypanosomiasis cases the parasites were found 
in the cerebro-spinal fluid, but in thirteen no parasites were seen, although in one case 
(No. 101) the fluid was examined on five occasions. 
If, however, those punctures in which the cerebro-spinal fluid was mixed with 
the blood in greater proportion than from three to four red cells to a field (Zeiss 1/6 
objective, No. 4 eye-piece, diaphragm removed), and in which the parasites were found 
by coverslip examination to be present in the peripheral blood on the same day as the 
puncture, be excluded, then we find that the above result is very different, namely, 
thirty-two cases, in sixteen of which the parasites were found in the cerebro-spinal 
fluid, and in sixteen they were not. The amount of cerebro-spinal fluid drawn off 
and centrifugalized at each operation varied from 10 to 30 or even 40 c.cm. This, if 
necessary, was not only centrifugalized a second or third time, but from one to six 
coverslip preparations of the resulting deposit were examined before a negative 
result was recorded. 
If the cerebro-spinal fluid is mixed with blood it has a slight yellowish tinge, 
and is opalescent or clouded according to the amount of blood it contains. If 
