4 DISTRIBUTION OF THE SPOTTED-FEVEE TICK. 



protection as is afforded by timber. Ticks have been found to be 

 especially abundant in localities "where there is much fallen timber 

 and brush. The immature ticks have been found to feed almost ex- 

 clusively on the small mammals, and adults on the large domestic 

 animals. Hence, the absence or scarcity of either of these classes of 

 hosts greatly influences the number of ticks occurring in a given 

 region. 



Mr. Vernon Bailey, of the Bureau of Biological Survey, has 

 pointed out that the distribution of a subgenus of the ground squir- 

 rels — namely^ Colobotis— corresponds very closely to the area in 

 which the spotted-fever tick occurs. The relation between the tick 

 and its hosts, as well as control measures, will be discussed at length 

 in a publication to be issued under the auspices of the Bureau of 

 Entomology, the Biological Surve}^, and the Montana Agricultural 

 College. 



THE IMPORTANCE OF THE DISTRIBUTION OF THE TICK. 



It is not desired to cause undue alarm regarding the danger from 

 Rocky Mountain spotted fever. Since, however, the malady is known 

 to occur in a number of the States where this species of tick is found, 

 and there is reason to believe that the disease is spreading, a knowl- 

 edge of the range of the species is im^Dortant. In fact there is good 

 reason to suppose that Rocky Mountain spotted fever may occur and 

 be transmitted to man in any region where this species of tick is 

 present if the disease is once introduced into a localit}^ by a tick 

 from a disease-infected region, or by man or some other animal sus- 

 ceptible to the disease. It may also be stated that the tick is of 

 some importance as a parasite of live stock. These considerations 

 make it imperative that the tick be kept under control in all regions 

 where it occurs and that steps be taken to lessen the danger of the 

 introduction of disease-infected ticks into uninfected regions. 



Approved : 



James Wilson, 



Secretary of Agncidture. 

 Washington, D. C., February 15, 1911. 



o 



