274: QUEENSLAND AGRICULTURAL JOURNAL. [1 Aua., 1901. 
IS THERE A NATURAL ME BRO INFECTION EXCLUDING THE 
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One might ask, for example, if the ingestion of virulent products taken 
from diseased animals is capable of inducing the disease. With this object in 
view, I made a series of experiments, in which I fed animals with hay damped 
either with blood very rich in Piroplasma, recently taken from diseased. beasts, 
or taken from twelve to tventy-four hours previously, or with emulsions made 
with all kinds of organs, such ag kidneys, spleen, liver, pancreas, marrow, brain, 
and, lastly, with the contents of the intestines or hemogloburinic urine. All 
the experiments were fruitless. Furthermore, these animals had not thus 
become immune. 
Exampie-—On the 17th April, 1899, a crossbred Durham bullock, eighteen 
months old, kept without food on the previous day, ate, with its rations of hay, 200 c.c. 
of blood of a beast that died during the night, and 300 c.c. of hemogloburinic urine. 
On the 18th it had another feed, damped with blood and urine of animals 
which had died of malaria. The blood of the subject of the experiment was examined 
daily, and the corpuscles counted twice a week. For the fifty days following the 
pommiengement of the experiment I observed nothing. The temperature was constantly 
normal. 
On the 7th October I injected ,}5 ¢.c. of blood beneath this animal’s skin. On the 
14th the temperature was 39°8 C.; on the 15th, 40°3 C. In the red blood corpuscles 
I easily found Piroplasma. In the evening the urine began to turn red. On the 16th 
the temperature was 41°5 C. The animal was very sick, the urine almost black. 
Hematozoa were numerous in the corpuscles. The animal died on the night of the 
17th October, and on autopsy being made, all the lesions of bovine malaria were 
found. 
The swallowing of young ticks of various ages up to complete maturity has 
always been shown to be inactive. 
Finally, we may consider the possibility of the transmission of the malaria 
by stinging flies, such as Stomoxes (S. calcitrans), Gad-flies (Labanus autum- 
nalis), &¢. 
IT have shown how it is easy to impart the disease by piercing the skin of 
an animal, and by rubbing the spot with blood very rich in piriform hematozoa; 
hence it would be reasonable to believe in positive inoculation of the malaria by 
flies, and yet, in practice, not one of my observations in the field or in the 
laboratory has confirmed this method of transmission. It is evident that there 
is a great difference between the puncture made by flies and our dermic¢ 
inoculation. It is necessary that at the instant the fly stings the diseased 
beast, its blood should contain a fairly large quantity of piriform hematozoa. 
On the other hand, when, after having stung a sick beast, the winged insect 
settles on a healthy beast, and buries its trunk in the skin, it inhales ; whilst 
in ous experiments, we seek to force the virulent liquid into the small cutaneous 
wounds. 
However that may be, if I believe inoculation of bovine malaria to be 
possible through the agency of stinging flies, I consider it extremely rare, the 
more so because the Stomoxes and the Gad-flies (or horse-flies) do not possess: 
the poison favourable to ticks. As to direct contamination by contact of healthy 
animals with diseased ones, without the intervention of ticks, this has never 
been authenticated in twenty experiments carried out with that view, whether 
there had been Stomoxes or not. 
GEOGRAPHICAL DISTRIBUTION OF BOVINE MALARIA IN THE 
ARGENTINE REPUBLIC. 
By the help of information gathered amongst station-owners who know 
their districts well, also from my colleague, Mr. Even, whose experience of ten 
years was valuable to me, and, lastly, thanks to my numerous journeys, I hay 
tried to separate on the map of the Argentine the infested from the immune 
regions. 
Ft A. reference to Plate XVI. will show that I recognise three zones: That 
of the North, where the boyine malaria exists in the endemic state ; that of the 
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