THE TICKS 



143 



countiy, the following brief descriptions of which are taken principally 

 from those given by ^lohler (Bull. No. 78, Bureau of Animal Industr}-, 

 1905; Farmers' Bull. No. 569, 1914). The parts described are those of 

 the adult female. 



1. Ixodes ricinus (Fig. 81). The Castor-bean Tick. Ixodes (p. 

 142). — The body is ovoid in shape, narrower anteriorly than posteriorly; 

 lead colored, with a diversity of 3'ellowish red, brown, or gray. Festoons 

 are absent. The mature female is three-eighths to seven-sixteenths of 

 an inch m length. The legs are thin and dark brown in color. The 

 capitulum and scutum are a shiny dark brown or' chestnut brown; 

 scutum pentagonal with prominent lat- 

 eral borders. The palpi are well de- 

 veloped and extend outward upon each 

 side. 



This tick has been collected from sheei\ 

 goats, cattle, horses, deer, dogs, foxes, 

 cats, rabbits, birds, and man. It i- 

 widely distributed in the United States. 



2. Ixodes hexagonus. The European 

 Dog Tick. Ixodes (p. 142).— The body 

 is oval in shape and of an ashy color; 

 festoons absent. The legs are longer and 

 more robust than those of the cattle tick. 

 The capitulum and scutum are brownish 

 red in color and similar to those of 

 Ixodes ricinus in shape. The palpi are 

 longer and more prominent than in the 

 cattle tick and, like those of Ixodes ridniis, extend outward. 



This species has been collected from dogs, cattle, sheep, foxes, rabbits, 

 squirrels, gophers, cats, birds, man, and other hosts in the Eastern 

 United States, but is less common in this country than the other species 

 here described. 



3. Dermacentor reticulatus (D. occidentalis). The Net Tick. 

 Dermacentor (p. 142). — The body is oblong oval, five-eighths of an inch 

 long, and of a deep brown or slate color. The legs are brown and of 

 moderate length. There are eleven festoons about the posterior margin 

 of the ])ody which in the adult become shallow or effaced. The scutum 

 has a silveiy-white metallic rust extending along the two sides and 

 posterior portion. 



Found on man, cattle, horses, sheep, and deer. In this country it 

 seems to be most common in the West, especially in California, Texas 

 and New^ Mexico. 



4. Dermacentor variabilis (D. electus, Fig. 82). The American 

 Dog Tick or Wood Tick. Dermacentor (p. 142). — This tick resembles 



Fig. cSl. — Ixodes ricinus — enlarged 

 (after Osborn, Bull. No. 5, Bureau 

 of Entomology, U. S. Dept. of Agr.). 



