It should be noted that argasid ticks in general are xerophilic 

 animals. Many students of their life cycle have failed to recognize 

 this important fact. Although in localities of extremely low rela. 

 tive humidity argasids may seek a somewhat more humid microhabitat, 

 these niches are seldom those with a significantly high relative 

 humidity. The few species extending into the humid tropics choose 

 dry niches in dry habitats ajid do not thrive away from these re- 

 treats. Within this range, individual species have varying degrees 

 of tolerance. 



Examination of bird nests, caves, bat roosts, animal lairs, 

 burrows, rodent nests, hyrax dens, and big game resting and rolling 

 areas in the Sudan will undoubtedly reveal vinrecorded or possibly 

 even \indescribed argasid species, Althovigh of considerable medical 

 importance and zoological interest, these ticks are not frequently 

 collected because specialized efforts and techniques are necessary 

 to obtain them. Sifting of soil or sand in animal burrows, caves, 

 or dens is often most f^uitf^ll, Examination of rock interstices and 

 searching under stones is also important in some situations. In- 

 vestigation of bird nests, especially those of larger birds, should 

 yield much interesting data. There is little doubt that at least 

 one Argas parasite of birds, eind Ornithodoros erraticus remain to 

 be found in the Sudan, in addition to 0, delajio'Si and some member 

 of the 0, tholozani group, ~ 



-49- 



