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ENTOMOLOGY FOR MEDICAL OFFICERS 



Europe, Asia, and Africa, and parasitic on mammals and 

 tortoises, and occasionally on lizards and birds. 



Dermatocentor, Koch ((5e/)^ia = skin ; x:eVTW/o = goader). 

 The rostrum is generally short, but sometimes the 

 pedipalps are almost as long as those of certain species of 

 Amblyomma and Hyalomma ; in such ambiguous cases the 

 distinguishing character of Dermatocentor is the large size of 

 the coxae of the fourth pair of legs. From all other ticks 

 with short rostrum Dermatocentor is distinguished either by 

 the quadrangular basis capituli or by the subquadrangular 

 2nd segment of the pedipalps. The scutum is often marked 

 with conspicuous golden spots. Neumann allows nine valid 

 species, distributed in Europe, Asia, Africa, and America. 

 Dermatocentor reticulatus var. occidentalis is said to be the 

 infective agent of Rocky Mountain Spotted Fever; in this 

 species the scutum is brown with white markings, the 2nd seg- 

 ment of the pedipalps has a recurved dorsal spine, and the coxae 

 of the fourth pair of legs are bluntly produced posteriorly. 



.chelicerae 



hyposfbme 



Fia. 121. — JQdpice^'kalus sanguineus, malo, ventral view. 



Hamaphysallis, Koch (al^xa = blood ; ^ii(raXXiy = bladder). 

 The species are, as a rule, easily distinguished by the form of 

 the 2nd segment of the pedipalps (Fig. 122), which has the 



