BIOLOGY 



After having collected mimerous specimens of Ixodes rasus 

 from many small mammals in Kenya, from sea level to 8000 feet 

 elevation, it was surprising to find this species so rare in 

 the Sudan. From Pearse*s (1929) report on Nigerian ectoparasites, 

 I. rasus appears to be common on small mammals there. The reasons 

 Tor these considerable differences in local populations remain to 

 be explained. 



Nuttall (1911) categorized I. rasus in the biological group 

 within the genus Ixodes in which^males and females are usually 

 found together on a host that either wanders or does not travel 

 far and in the subgroup in which the sexes are often found in 

 copula on the host. Present evidence partially supports the 

 inclusion of Ixodes rasus in the last subgroup ajid careful col- 

 lecting may subsequently prove that this species should be so 

 considered. 



Systematic search probably will show Ixodes rasus to be a 

 common tick in many parts of tropical Africa. Examination of 

 rodents in certain areas should prove fruitful. Seeking for 

 every tick on a variety of animals will undoubtedly reveal a 

 few, small inconspicuous, weLL-hidden Ixodes ticks along with 

 more apparent, more numerous, larger, and more colorful ticks 

 of other genera. 



(Questions concerning the biology of Ixodes rasus in its 

 varioiis forms (i.e. subspecies) offer a challenge in one of the 

 most fascinating zoological areas of the world. 



DISEASE RELATIONS 

 Unstudied, 



RMARKS 



Schvilze (19^1) noted certain features of the haller's organ 

 of I. rasus (cf. also K. W. Neumann 194-3). A comparison of this 



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