BIOLOGY 



Judging from its considerable geographical range, this spe- 

 cies is able to adjust to marked climatic variations only par- 

 tially modified by protected cave environment. 



I. vespertilionis is rare on bats in B^uatoria Province east 

 of the Nile. Over a thousand bats, representing almost every spe- 

 cies in Eastern Bquatoria, have been carefully searched without 

 finding more than the single specimen listed above. There has 

 been little opportunity to examine carefully many caves. 



Males have been collected only from caves and other retreats 

 in which bats assemble. No males have been fo\md on bats. Nuttsill 

 and Warburton (1911) postulated that males may either feed very 

 rapidly and then leave the host or that they may not feed at all 

 Nevunann (1916) believed that the variotis degrees of engorgement 

 in which male specimens are found might not necessarily prove 

 that males do feed but rather may be an indication of degree of 

 nymphal feeding. This conclusion is based on the atrophy of the 

 male hypostome in comparison with its robust development in fe- 

 males and in immature stages. 



Neumann (loc . cit .) mentioned the preponderance of numbers of 

 males in relation to females and immature stages in collections 

 and surmised that this may be due to the conspicxiousness of the 

 male's vagabond search for females. Females secrete themselves 

 between stones of the caves to digest their blood meals. They 

 probably oviposit in these niches, though this is not certain. 

 Engorged nymphs are sometimes found in similar situations. 



When females are found on the host, immature stages are 

 frequently found with them. Feeding is probably comparatively 

 rapid, otherwise it is logical to assume that females and nymphs 

 would have been more frequently reported from bats. 



Arthur's (1956A) comparison of data from Switzerland and 

 from Macedonia leads him to believe that, because there is a 

 reasonably high catch of partially and fully engorged ticks be- 

 tween October and Janviary and a number of vinfed nymphs and fe- 

 males during the siunmer, feeding is accomplished mainly during 



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