118 DEPARTMENT OF AGHICULTUKE. 



paign, and in a host of other places, southern cattle, purchased last fall, were placed with 

 indigenous stock, have remained with them ever since, and have induced no disease. This 

 is very generally known and admitted. A reporter from Cedar County, Missouri, writing 

 in 1866, said: &quot;It is thought that our cattle would not take the. disease in the winter sea 

 son, but this may be only conjecture, as no large droves have yet been driven here from 

 the South in the winter.&quot; Of late years, however, there has been an effort to drive from 

 Texas for the October and November markets, and we have not heard of a single case 

 where stock-drivers, up at that time, had done any mischief in Illinois or Indiana. Nip 

 ping frosts may and do kill the disease, by destroying the pasture, and compelling people 

 to feed their cattle. This completely arrests that method of transmission, which I believe 

 to be the main or only one. As soon as western stock is removed from the pasture on which 

 Texan cattle have been fed, it is safe; and this is an unanswerable argument in favor of 

 the views I have promulgated since the time of my first observations. It is not the breath, 

 nor the saliva, nor cutaneous emanations which are charged with the poisonous principle, 

 but the fieces and the urine. 



It has, however, been very generally remarked that Texan cattle are covered with 

 the tick. I owe to the kindness of C. V. Riley, esq., State entomologist of Missouri, a 



drawing of the tick as found on Texan cattle. In the annexed 

 engravings are an upper and an under view. As the legs do not 

 alter in size in proportion to the body, a view has been given 

 of a smaller specimen between the two. This tick belongs to 

 the Class Arachnidce, Order Trachearice, and Family Izodidce. It has eight fine, jointed 

 legs. It is not confined to cattle in the South, and is seen in many woodland pastures of 

 the United States. For convenience, and to distinguish this species from Ixodes reticula- 

 tus, I propose to call it Ixodes indentatus, from the peculiar indentations on the body and 

 absence of stripes. These ticks fasten on the bodies of native cattle, and breed. The 

 young ticks are distributed in myriads on the grasses, and it has been supposed that the 

 grasses are thus poisoned.* 



The &quot;tick theory&quot; has acquired quite a renown during the past summer; but a little 

 thought should have satisfied any one of the absurdity of the idea. 



1st. Ticks are not easily fenced on a piece of land by a wood fence, as cattle are. A 

 wood fence sufficiently isolates cattle to prevent splenic fever. 



2d. We have seen Texan cattle both alive and dead, and also dead western, quite 

 free from these parasites. There has been no relation whatever between the abundance 



* Tim following remarks on the Ixodoi 1ioi-in are from ( . V. Kiloy, St. Louis, Missouri : 



Ij-odix botix, (Kiloy.) A reddish, coriaceous, flattened species, with the body oblong-oval, contracted just behind 

 the middle, sur.l witli two longitudinal impressions above this contraction, and three below it, more especially visible 

 in the dried specimen. Head short and broad, not spined behind, with two deep, round pits. Palpi and beak together 

 unusually short, the palpi being slender. Labium short and broad, densely spined beneath. Mandibles smooth above, 

 with terminal hooks. Thoracic shield distinct, one-third longer than wide, smooth and polished ; convex, with the 

 lynite medial convexity very distinct. Legs long and slender, pale testaceous red ; coxa not spined. Length of boil v, 

 .l. r &amp;gt; of an inch; width, .(IS) of an inch. Missouri Coll., ( . V. Kiley. 



This is the cattle tick of the Western States. Several hundred specimens, in dill rrcnt stages of growth, have also 

 been received from I nlvon, west coast of Nicaragua, taken from the horned cattle, and on a species of Itaii/jiroi-ta, by Mr. 

 J. McNeil. They preserve the elongated tlatteucd form, with the body contracted behind the middle, by which this 

 species may be easily identilied. The largest specimens measure .50 by .:&amp;gt; of an inch. When gorged with blood they 

 are nearly as thick through as they are broad. In the freshly-hatched hexapodous young, and the young in the next 

 stage of growth, the thoracic shield is one-third the size of the whole body, which is pale yellowish, with very distinct 

 crcniilations on the hinder edge. The fourth pair of legs is added apparently at the first moult. It is called &quot; garapata 

 by the inhabitants of Nicaragua. 



