12 



CIRCULAR 338, U. S. DEPT. OF AGRICULTURE 



The Americac dog tick (fig. 8) usually occurs as an adult tick on 

 dogs, the earlier stages (those of seed tick and nymph) occurring on 

 various small mammals. It attaches to various parts of the body, 



but displays a preference for 

 the ears. When fully en- 

 gorged with blood the female 

 tick is almost half an inch 

 long and of a bluish color, 

 with a reddish-brown shield 

 with white markings on the 

 back near the head. This 

 species occurs in the eastern 

 half of the United States, in 



FiGUEE 8.— The Amsrlcan dog tick or wood tick, parts of the WCSt COast, and 

 Bermacentor variabilis. Left, engorged female; right, ^ • ii„ i i • ,i • 



male. Dorsal views. Enlarged. From Banks, 1908. Occasionally elseWUere m tlUS 



country. 



The brown dog tick (fig. 9) occurs on dogs as seed tick^ nymph, 

 and adult. It frequently attaches inside a dog's ears, sometimes deep 

 in the ear canal. The young ticks 

 are Ukely to be abundant m the 

 long hair on the neck, but any stage 

 may occur on almost any part ot 

 the body, including the spaces be- 

 tween the toes. In this country 

 this tick occurs in the South, being 

 reported from Texas, Louisiana, 

 Mississippi, and Florida, but it 

 may be found farther north, being 

 reported from Ohio, Pennsylvania, 

 and New York. Its occurrence 

 in these Northern States is due, no 

 doubt, to the fact that dog owners 

 have transported ticky dogs, mostly 

 hunting dogs, from the South to 

 the Northern States. It appears 

 to have taken up the habit of 

 living indoors over winter as an 

 adaptation to cold winters, and 

 accordiog to F. C. Bishopp, of the 

 Bureau of Entomology, and reports 

 from various persons, causes seri- 

 ous trouble by establishing itself 

 in kennels and about houses. 



Symptoms. — Ticks cause local 

 irritation at points of attachment, 

 and dogs commonly bite or scratch 

 these places. In heavy infesta- 

 tions the injury may be serious. In addition to the local injury 

 there is a loss of nervous energy from irritation. The tick buries 



Figure 9.— The brown dog tick, BMpiceplialus 

 sanguineus: A, Male; B, anengorged female. 

 Enlarged, From Mcintosh, 1931. 



