In Ervpt it is certain that there is an urban race, attacking 

 dogs alniost without exception, and a field race that parasitizes 

 rodents, hedgehogs; hares, and, when available, doirestxc animals 

 The field race occurs only on the Mediterranean littoral, rarely 

 in scattered desert areas and oases, and in conjunction with a_ 

 few rodents of cultivated areas. The domestic race is comraon m 

 urban and settled areas; along with hyalommas it is almost the 

 only ixodid ever found in those desert areas that support some 

 grazing. However, the propensity pf the domestic race for seeking 

 out favorable niches of human habitations and domestic animals, 

 which are always sheltered from thieves and from pedators in 

 th^se areas causes it to be irore localized than are its ubiquj- 

 l: freld compSIons, such as H. excavatum . The -tual r^^^^^ 

 of urban and field races we hope to determine as early as possible. 



In tropical and southern Africa, it appears that R. s. sang^ 

 neus is generally distributed through the warm and humid zones of 

 THTcontfSnt. In the more arid parts of this area, its presence 

 or absence se^ms to be dependent largely on human cultural Patterns, 

 especiaSJ of pastoral tribes (see Cattle Hosts, page 698). Whether 

 SS and field races exist in Africa soutTTTTthe northern deserts 

 is at present difficult to determine from available data. 



Most observations on host parasite relations presented below 

 apply to domestic populations. 



Larvae attach to the host mostly in hairy places but may oc- 

 cur ^;^h:re on the body. N,-mphs are found indiscrimin^ely among 

 the fur or elsewhere. Adults are especially common on and in the 

 ea^s tho^h they may attach along the nape, between the toes or 

 Z^LvTlse. Specimens on birds are usually found on the crown 

 or about the ears, eyes, or bill. 



Females often creep upward on walls after ^^f^j-^e ^J^„J°^^ 

 and mav hide tightly wedged in narrow cracks as high as fifteen 

 ?;tt^love the gromd (C^istophers 190X). Eggs aredeposited 



tLrTeL the ground or high above it, in crevices in woodwork, 

 SerprafterfvStewash, or^aper, or out-of-doors, under stones 

 (Lewis 193A, Roberts 1935, du Toit 1947). 



Tremendous infestations frequently occur. ^^ Cairo, one may 

 see houses '^crawling with" kennel ticks and mongrel dogs with more 



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