THE AMERICAN DOG TICK. 191 
mm. long (from tip of palpi to base of emargination of scutum); 
scutum 0.255 mm. long by 0.32 mm. wide. 
Egg.—Ellipsoidal, pale yellowish brown, shining, smooth. The 
average size of those measured was 0.527 by 0.379 mm. 
HOST RELATIONSHIP. 
The host of the type is not recorded. The dog is the most common 
host of the adult stage of this species. Out of 112 lots collected by 
agents of the bureau the following numbers of lots were taken on the 
different hosts listed: Dog 62, fox squirrel 9, raccoon 6, opossum 6, 
ox 5, badger 3, coyote 3, skunk 3, deer 2, man 2, wolf 2, ass 1, Mexi- 
can lion (Felis hippolestes aztecus) 1, fox 1, hog 1, horse 1, rabbit 1, 
weasel 1, wild cat 1. The lot from the Mexican lion, consisting of 
9 males and 3 females, was collected by Mr. D. K. McMillan at Ray- 
mondville, Tex., November 20, 1910. 
No larve known to be of this species have been collected, but a 
considerable number of nymphs have been taken on fox squirrels and 
one lot was collected on a swamp rabbit (Lepus aquaticus). Adults 
of both sexes were taken on the fox squirrels along with the nymphs. 
Most of the lots collected on this host were taken by Mr. J. D. Mitchell 
in March and April, 1909. In rearing experiments larve attached to 
a bovine, but failed to attach to dogs, even after several attempts 
were made. 
GEOGRAPHICAL DISTRIBUTION. 
(Fig. 16.) 
The locality from which the type was described is not recorded. 
The determination of the distribution of this species is complicated 
through questionable identification due to the fact that, superfi- 
cially, it closely resembles several other species. 
The species is common throughout the eastern half of the United 
States. It is recorded from Alaska, Labrador, Ontario, and Nova 
Scotia on the north and its range extends southward through the 
United States to the Gulf coast. There is also one record from 
Mexico. Although the species has been listed from Colorado, New 
Mexico, and Arizona, our investigations indicate that it does not nor- 
mally occur in those States. There is, however, a considerable area 
in western California and southwestern Oregon where the species is 
very common. In this region and in the Central and Southern States 
the species appears to occur most abundantly. 
LIFE HISTORY. 
Observations on the biology of this tick have been published: by 
Morgan (1899, pp. 133, 135), Hunter and Hooker (1907, pp. 50-51), 
and by Hooker (1908, p. 47). 
