TRYPANOSOMES, TRYPANOSOMIASIS, AND SLEEPING SICKNESS 19 
Anaemia may be a prominent feature. The blood count ot one cat was, reds, 
8,600,000; whites, 6,000 ; haemoglobin, seventy-eight per cent. ; on the twenty-ninth 
day of infection, reds, 3,470,000 ; whites, 14,400 ; haemoglobin, thirty-eight per cent. 
Its weight had decreased three hundred and twenty grammes during this time. The 
parasites in this animal were numerous, at times three to a field were seen. Auto- 
agglutination is a noticeable feature both in the acute and the chronic types of the 
disease. 
Kittens are very susceptible, the parasites appearing early and generally persisting 
in large numbers until death. The anaemia is severe. Loss of weight and stoppage 
of growth occurs. A high temperature is noticed. The duration of the disease is 
from three to seven weeks. Purulent conjunctivitis is common. 
Rabbits 
The incubation period has not varied markedly ; from the figures given in the 
preliminary report five to fifteen days. Some of the rabbits have lived one hundred 
and fifty to two hundred and seventy-three days; these have had a chronic, mild 
infection. Average duration fifty to one hundred and twenty-eight days. 
Guinea-Pigs 
The disease varies, many of the animals have only shown the parasites after one 
to three months or more. The trypanosomes have then continued present in large 
numbers, death occurring fourth, ninth, and sixteenth weeks after the appearance of 
the parasites in numbers. Rupture of the spleen has caused death in four cases, in 
every instance the blood was full of trypanosomes and the spleen acutely swollen. 
Morphology of the Parasite 
Dutton and Todd, Laveran and Mesnil, Bruce, and others have described 
the parasite. Both Dutton and Todd, Laveran and Mesnil, and Bruce have had 
opportunity of comparing the trypanosomes found in the blood with those parasites 
found in the cerebro-spinal fluid and those present in the blood of inoculated animals. 
All groups of observers have agreed that they can determine no marked differences. 
All agree that the parasites in the cerebro-spinal fluid are often vacuolated. As 
Laveran and Mesnil point out and illustrate in their work (Fig. XLII, Nos. 1, 2), 
and Dutton and Todd (PI. I, Fig. 1), the trypanosome may contain large vacuoles. 
Laveran and Mesnil ascribe it to the parasite being poorly fixed, and show that with 
very serous blood such a condition is common. Such being the case it is only natural 
that films made from the cerebro-spinal fluid will contain many of these vacuolated 
forms. 
We have compared the trypanosomes in the same way as these observersand can find 
nodifference between the parasite present in the cerebro-spinal fluid and blood of patients, 
