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cultivated lands especially in the eastern States. Amblyomma ameri- 

 camim (lone star tick), found on cattle, dogs, horses, sheep, goats, 

 hogs and man. and very widely distributed in the States. Ornithodorus 

 megnini (ear tick), is found in the ears of cattle, horses, mules, asses 

 and other animals in the south or west. Argas mimatus (fowl tick) 

 has been observed on cattle once only, but is frequently found on 

 fowls, turkeys and other birds in the south. Ixodes hexagonus 

 (European dog tick) has been collected from dogs, cattle, sheep, foxes, 

 rabbits, squirrels, gophers, cats, birds, man and other hosts in eastern 

 United States. 



In certain cases in the south, animals have suffered from the disease, 

 but no ticks have been found on them ; the author explains this on 

 the hypothesis that the animal's blood was already infected with the 

 microparasites and under normal conditions was immune from Texas 

 fever, but as a result of a lowered vitality caused by some other disease 

 or by privation, injury, rough handling, etc., this immunity has become 

 reduced and finally overcome. The experiments of the Bureau of 

 Animal Industry show that the blood of an immune animal may contain 

 this microparasite for at least 13 years after removal of all sources of 

 infection, so that such a recurrence may be termed a relapse. 



Under certain conditions, as when living on horses, mules, asses or 

 sucking calves, fever ticks lose their infectiousness through the host 

 being a non-susceptible animal, and the progeny cannot produce the 

 disease, though they can easily become infectecl. Non-infected ticks 

 are so uncommon that it is necessary to treat all fever ticks as capable 

 of transmitting Texas fever. The author points out that attachment 

 to a host is essential in order that fever ticks may come to maturity, 

 while other North American ticks can mature without a host. 



Other injurious effects may be produced by cattle ticks, apart from 

 the fever. As a result of continuous loss of blood young animals mav 

 never develop fully, remaining thin, weak and stunted, and easily suc- 

 cumbing to other diseases owing to their lowered vitality. In milch 

 cows the debilitating influence of the numerous ticks is shown in a 

 greatly reduced milk supply, the loss averaging about one quart a day. 

 In some cases the large number of bites over a limited area of skin may 

 be followed by infection with pus-producing organisms, giving rise 

 to abcesses. The discharge from such sores, or in some cases the mere 

 oozing of blood serum through the incision made by the mouth-part 

 of the ticks, keeps the hair moist and matted together, and such places 

 are liable to become fly-blown, sometimes with serious consequences. 



In dealing with the economic aspect of the tick problem, the author 

 points out that the animals coming from infected districts and sold 

 in the southern pens of northern stockyards realize ^ to | a cent 

 per lb. less than the quoted market price, thus reducing the price per 

 head by about $1.50. Hides that have been infected with ticks are 

 graded as No. 4 quality, while if free, they would have been graded 

 as No. 2 ; the difference in price is 3 cents per lb., so that with an 

 average weight of 42 lb., the loss is §1.26 per hide. It has been shewn 

 that the cost of tick eradication is 50 cents a head. 



About 10 per cent, of all northern cattle taken south die of Texas 

 fever, even after they are immunised by blood inoculations, and about 

 60 per cent, of these cattle succumb to this fever when not so treated. 

 A further disadvantage to the souther farmer is that his animals are 

 barred from most of the exhibitions in the north, and the northern 



