292 QUEENSLAND AGRICULTURAL JOURNAL. [1 Aprin, 1902. 
and bowels, in acute cases, are generally somewhat reddened. The many plies 
will be impacted, and the lining will peel off. The bladder in these cases 
contains a cherry or wine coloured liquid. The blood will be thin, but will 
coagulate. There will be no disease of the skin or swellings on the body as 
occur in some other diseases—notably as in anthrax, which has some symptoms 
resembling those of Texas fever. The gall-bladder will contain, instead of the 
usual green, free-flowing liquid, a dark, semi-coloured mass. 
The presence of the foregoing symptoms and post-mortem appearance in 
animals dying or dead of a mysterious disease is sufficient to cause one to 
suspect Texas fever. Additional evidence would be had, if, at the same time, the 
cattle-tick were found upon the animal, or if close examination of the skin of 
the udder, escutcheon, or dew-lap showed little reddened, rough areas caused 
by the tick bites. 
If more scientific methods can be applied, a microscopic examination of the 
blood will show an enormous decrease of the red-blood corpuscles, from 
5,000,000 per cubic millimeter, the normal number, to as low as 2,000,000 per 
cubic millimeter. The corpuscle will also exhibit great changes in size and 
shape. They will appear shrivelled and crenated. Ifa drop of the blood be 
smeared upon a piece of glass, allowed to dry, subsequently wetted with methy- 
lene blue and examined with a microscope of 1,000 diameters, the real cause 
of the disease can be observed. The larger white corpuscles will be stained 
blue, as will also any bacteria which may be present. The red cells will not 
have taken up the stain, but willappear as round, yellowish, transparent bodies 
much smaller than the white corpuscles. Frequently inside the red corpuseles 
will be noted very small blue-stained points; sometimes they may be larger, 
pear-shaped, and in pairs. The same bodies are also found outside the red 
corpuscles. This little body is the cause of the fever. It lives inside the 
red cells, destroys them, and finally kills the animal. Jt is its destruction of the 
red cells of the blood, and the efforts of the kidneys to eliminate the débris 
thus formed from the blood, that causes the red water contained in the bladder, 
and gives rise to the name “red-water disease” used by some persons. The 
little speck mentioned above is an animal—the lowest form of animal—and 
consists of a single cell. It is a member of the group of protozoa, and has been 
named by Professor Smith, its discoverer, Pyrosoma bigeminum. This parasite is. 
harboured and transported by the ordinary cattle tick whose ancestors passed. 
their lives upon a cattle infected with the germ of Texas fever. Whether or 
not the tick is the only carrier of Texas fever is not known; but there seems 
to be no reason why any insect which had bitten infected cattle could not carry 
the disease to a susceptible animal. It is now known that the cattle tick can 
be deprived of its power to produce Texas fever by being reared upon animals 
which are insusceptible to the disease. Our ordinary cattle tick is found also 
upon Porto Rican cattle. Experiments made by Dr. E. C. Shroder, of 
Washington, D.C., show that the Porto Rican cattle-tick, although the same 
specifically as ours, is incapable of causing Texas fever. This being the case, 
a single ticky animal arriving in Porto Rico from the United States would 
probably start up the disease in that island and destroy its cattle industry. 
The cattle tick has a very large geographical distribution in the United 
States. The federal quarantine laws define as being permanently infested with 
the tick all those States or portions of States in which the cattle tick is 
found—z.e., Virginia, North Carolina, South Carolina, Georgia, Florida, 
Tennessee, Alabama, Mississippi, Arkansas, Louisiana, Indian ‘Territory, 
Oklahoma, ‘Texas, California, portions of the States through which the 
line runs may be exempt, and it is changed slightly from year to year; 
for instance, sixteen counties in Western North Carolina are placed north 
of the line, the tick not being found in them. In other words, the distri- 
bution of the tick is limited to those regions where the winters are not severe 
enough to freeze the eggs. It will be thus readily seen that no hard-and- 
fast line can be drawn, and the location of the quarantine will always be a 
source of contention between the Federal ard State Governments in those 
States through which the line is run. Although the quarantine maintained by 
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