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(i) Natural infection.—It would appear that stock-owners do not 
recognise more than one form of ‘ fly disease,' and that the animals 
infected by this trypanosome are considered as cases of ordinary fly 
disease. Of these five animals, that first seen was kept under 
observation for ten days at the original camp, and was later 
purchased and brought to that at which our experimental work was 
conducted. 
Both animals which showed a mixed infection died within three 
weeks of diagnosis. The one detected just before leaving Broken 
Hill was alive, but considerably thinner six weeks later ; whilst the 
fifth was reported to have died in August, seven weeks after parasites 
were seen, at which time it was in good working condition. 
Case No. VIII.— Bull, aged about five years, (vide chart vii.) No very 
reliable history of this case is available, but it appears that this animal, with the 
rest of the herd, had been grazed away during the rainy season of 1906-1907, and 
had pas^ed through fly areas on the way home in February, and that since that date 
it had gradually lost condition. 
On examination, it was emaciated and hide-bound, signs of excessive 
lachiymation were present and the conjunctivae showed a few small petechiae, a 
condition seldom noted in animals infected with T. dimorfhon. Prescapular and 
precrural glands enlarged *, abdomen tucked-up ; no oedema, but the bull presented 
all signs of tr5rpanosomiasia, from which it was suspected of suffering by the 
owner. The case was under observation for 26 days between July loth and August 
15th. 
A noticeable feature in the temperature is the great daily variation, as much 
as S'4° F. being met with. By joining up the evening or morning registrations the 
‘curve’ produced would not be great; there is no suggestion of a paroxysm, and 
the mean of morning and evening temperatures would not vary much from normal. 
Trypanosomes are always scanty, from one to ten to a cover-glass was the 
usual number, only exceeded on four occasions, when approximately one in ten 
fields was seen. The great rapidity of the organism rendered any degree of 
accuracy in counting impossible, for their presence was generally only ascertainable 
by the slight displacement of corpuscles which accompanied their hurried passage 
across the field, a passage it was impossible to follow by any ordinary movement 
of the slide. With such an organism it is very probable that the one or two 
organisms present in a preparation would not come within the field of vision. On 
two occasions when they were not seen, centrifugalisation showed them to be 
present, and in one case a trypanosome was found in a thick-stained film. We 
would consequently suggest that the trypanosomes were almost constantly present 
in the peripheral blood and that with this parasite there is no great paroxysmal 
increase, and their detection is to a more considerable extent a matter of chance 
than is usual in the other forms of Trypanosomiasis. 
During the 25 days of observation, parasites were seen on i6 occasions, eleven 
were m.irked -t-. one -H-. and four three of these latter occurring in the 
last week of life, and the other after the animaf had been driven 22 miles in two 
days to the camp. Two days previous to death extreme weakness was manifest, the 
patient falling down several times and showing great difficulty in rising. 
Post-mortem commenced 15 minutes after death. Rigor mortis distinct, 
mucous membranes pale, and a few petechiae on one conjunctiva. Skin closely 
