A. C. Coles 
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measurement of 16'8 x 3‘8 fx. The trypanosomes in the circulating blood 
probably have a length of at least 20 /z, excluding the flagellum, and 
this was the size of the trypanosome that was found in the first day 
culture.” 
Principal characteristics of Trypanosoma americamim (from the 
Sleeping Sickness Bulletin, Vol. iv, p. 150): “It is a large trypanosome: 
a total length of 75/r is by no means uncommon. The undulating 
membrane is very short: the kinetonucleus may be in front, alongside 
or behind the trophonucleus, but the two are always close together. 
The trophonucleus is at the junction of the anterior and middle thirds: 
hence the shortness of the undulating membrane.” 
As to the rarity of the trypanosomes, the author writes—“ Here it is 
seen that the smallest quantity of blood to give a positive result was 
five drops, or 0‘3375 c.c., and that this result was obtained only once 
out of three trials. Assuming 6,000,000 red cells and 10,000 leucocytes 
per cubic millimetre, we find as a possible proportion one trypanosome 
for 2,022,000,000 red cells and 3,370,000 whites. Hence to find the 
trypanosome in the circulating blood would be merely a piece of good 
fortune. Further, culture 444, containing 9 c.c. of blood, was negative, 
yet this amount of blood contains 90,000,000 leucocytesh” 
Trypanosomes found in a Goto. For some considerable time I have 
been making a systematic examination of the blood of domestic animals, 
small mammals, birds, fish, etc., and I asked my friend Mr J. S. Wood, 
Veterinary Surgeon, of Parkstone, to send me any blood films from 
diseased animals and particularly from cases of redwater fever in 
cattle. These films were received air dried, unfixed and unstained, and 
were afterwards stained with Giemsa’s stain. I should like here to 
express mv thanks to Mr Wood for the trouble he has taken on mv 
behalf. 
After a large number of blood films had been examined with negative 
results, I received from Mr Wood four films taken at 9.30 a.m., June 3, 
from a cow presenting symptoms of redwater fever. These films showed 
the presence of Piroplasma bovis in comparatively small numbers, only 
about 2 “/o of the red corpuscles being infected. (I say a small percentage, 
as during 1906 I received blood films from Mr T. B. Goodall taken from 
a cow with redwater fever, in which 23| 7o of the corpuscles contained 
Piroplasma.) 
1 See Trypanoplasma sp. Bowhill, 1909, and T. rutherfordi Hadwen, 1912, observed in 
Cows at Mount Lehman, British Columbia (Watson and Hadwen, Parasitology, this vol. 
p. 24, Feb. 1912). Ed. 
