162 
Biology of Dermacentor 
accompanying map (Fig. 1) indicates the points from which we have 
obtained specimens, as well as the probable distribution of the species 
in the United States. Little is known regarding its distribution in 
Canada, although it undoubtedly occurs commonly in much of the 
southern part of the Dominion. Dr C. Gordon Hewitt states, in his 
report for 1911 (p. 225), that this tick was taken at Huntingdon, B. C., 
from a horse which had been imported from Elgin, Oregon ; also in 
Quebec from elk brought from Wyoming. The following are the 
localities, arranged by States, from which we have received specimens 
during these investigations: 
Arizona: Patagonia. 
California : Coarsegold, Glen Ellen, Grass Valley, Hollister, Yoeumville. 
Idaho: Myers Cove, Nezperee, Waha. 
Montana : Aldridge, Canton, Cascade, Dupuyer, East Helena, Elizabeth, Eureka, 
Florence, Fridley, Hall, Jocko, Lo Lo, Paradise, Plains, Pony, Bimini, 
Rollins, Somers, Thompson Falls, Winston, York. 
New Mexico : Cimmaron. 
Oregon: Ashwood, Burns, Corvallis (?), Eagle Point, Flora, Gibbon, O’Neil, Riverside, 
South Umpqua, Tiller, Umpqua, Viewpoint. 
Texas : Fort Davis, Marathon. 
Utah : Whiterocks. 
Washington: Fruitland, Gray, Lakeside, Silcott, Stratford. 
Wyoming: Jackson. 
In general this species appears to be most abundant in the mountains 
or on more or less timbered uplands. As is shown in the list of 
localities, the tick has been collected from the extreme northern to the 
extreme southern part of the United States. It appears, however, to be 
much more numerous in the northern latitudes. It has been taken 
during our investigations at altitudes ranging from 227 feet to as high 
as 7000 feet above sea level. 
Hosts. 
Since this species does not drop from the host to moult, the animals 
upon which adults have been taken must be considered as hosts of the 
immature stages as well. 
The host of the type specimens is the moose. The young moose 
from which the types were taken was reported to have been heavily 
infested. The elk or wapiti is also commonly attacked and the beaver 
has been recorded as a host. We have found the horse to be the 
preferred host among domestic animals but the ox is frequently 
infested. 
