that the messy area in which adults usually feed influences to some 

 extent the numbers of red ticks represented in collections made by 

 Europeans though this is seldom a deterrent to "unspoiled" African 

 assistants. An exception to the above statements, however, was 

 made by Meeser (1952), who noted that red ticks on the impeila 

 antelope of southeastern Transvaal is infested on the genitalia 

 and shanks and almost nowhere else on the body. R. e. evert si , 

 together with B. decoloratus, are the chief tick parasites of 

 this common anTelope there. 



Theiler's (195QB) study of the distribution of the red tick 

 in South Africa shows that it is present in all types of forest, 

 in all parklands except dry ones, and in all types of grasslands. 

 It maintains itself with difficulty in shortgrass country sind is 

 generally absent from desert-shrub areas, but may persist in thorn 

 country and in mixed desert- shrub grassland. Altitude and low 

 temperatiire do not limit the red tick, but rainfall below ten or 

 fifteen inches per annum seems to be a limiting factor. There 

 appears to be no seasonal variation in the activities of this spe- 

 cies. 



In parts of Africa warmer than South Africa, a son^what higher 

 critical level of anntial rainfall is probably necessary for the red 

 tick to maintain itself, but definite limits have not yet been as- 

 certained. 



As already noted, another subspecies (miiaeticus ) takes over 

 from this subspecies in the arid areas of southwestern Africa but 

 both are fotind together in the savannahs of western equatorial 

 Africa. Such evolution of a rhipicephalid species in Africa is 

 as unusual as the red tick's morphology and as its life cycle. 



In Kenya, the red tick appears to be somewhat more adaptable 

 than in South and West Africa. There it occurs in the deserts of 

 Northern Province, in coastal areas and open plains, as well as 

 in forests above 8000 feet altitude; "in fact almost any- 

 where" (Wiley 1953). 



Wilson (1953) noted that the red tick occurs in both the same 

 areas as the R. pravus - A. gemma association (cf . page 68l) and 

 the R. appendiculatus - AT variegatixm association (cf . page 27^). 

 While absent from wet zones of Ny as aland and Tanganyika, it is 

 the dominant species in the Masai grasslands and occurs seasonally 



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