SPLENIC OR PERIODIC FEVER OF CATTLE. 121 



over the country duriug these mouths '? The second is tlie main reason ; 

 but it is impossible for me to reconcile many observations which I have 

 ma<le with the idea that heat does not favor the development of the dis- 

 order. It is not sufficient to name it, but it is asserted by practical men 

 that Texan cattle can be handled most safely \A-hen the summers are wet 

 and cool. The wet may wash the grasses, but the cold seems to lavor a 

 constitutional resistance to the attacks of the disease. A record of the 

 cases which demonstrate that Texan cattle can be freely placed with 

 western stock in winter would fill a volume. At Brondlands, Hickory 

 Grove, near Champaign, and in a host of other places, southern cattle, 

 purchased last fall, were placed with indigenous stock, have remained 

 with them ever since, and induced no disease. This is very generally 

 known and admitted. A reporter from Cedar County, Missouri, writing- 

 in 18(16, said : " It is tliought that our cattle w^ould not take the disease 

 in the winter season, but this may only be conjecture, as no large droves 

 have yet been driven here from the south iu the winter." Of late years, 

 however, there has been an effort to drive from Texas for the October 

 and ]SroAember markets, and we have not heard of a single case where 

 stock-drivers, up at that time, had done any mischief iu Illinois and 

 Indiana. Nipping 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 deprived of the pasture ou which 

 Texans have been fed, they are safe ; and this is an unanswerable argu- 

 ment 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 emana- 

 tions, which are charged with the i)oisonous principle, but the fieces and 

 the Tiriue. 



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 in St. Louis, a drawing of the tick as found on Texas cat- 

 tle. In the annexed engraving is an upper 

 and an inider view. As the legs do not 

 alter in size in proportion to the body, a 

 view has been given of a smaller specimen mmji^ nat.size 

 between the two. This tick belongs to the Fig. is. 



arachnidte, subdivision tracheariie, and family ixodide. It has eight 

 fine, jointed legs. It is not confined to cattle in the south, and is seen 

 iu many woodhind pastures of the United States. For convenience, 

 and to distinguish this species from Ixodes reticulatus, 1 proptDse to call 

 it Ixodes indentafus, from the peculiar indentations on the body and 

 absence of stripes. These ticks pass to the bodies of native cattle, and 

 ■ breed. The young ticks are distributed iu myriads ou the grasses, and 

 it has been supposed that the grasses are thus poisoned.* 



*For the scientitic desciiptiou of this iuaect see Mr. Riley's remarks ou the Ixodes 

 Bovis, \>. 152. 



