Hares (Tendeiro 1951A, Santos Dias 19520,195^; Stdan records 

 above ) . 



Rodents (Mastomys coucha , Aethonys namaquensis auricomls, and 

 A. cbrysophilis j (Theiler and Robinson 1953bJ. 



Insectivores ^Elephant shrews, Elephant uliis rupestris and 

 Nasilio br ac hyr hync hus (Theiler and Robinson 1953BJ. ElepHantulus 

 ftiscipes and E. rufescens hoogstraali (Stdan records above ) , and , 

 species not indicated, from Tanganyika (Hoogstraal 19$/iJC) 7 



BIOLOGY 



Life Cycle 



Wilson (I95OB) was unable to rear R. pravus under ordinary 

 atmospheric conditions in the laboratory. Theiler and Robinson 

 (1953B) also foiind this tick difficult to rear, but consider that 

 it is probably a three-host type. Lewis, Piercy, and Wiley 

 (1946) had difficiilty in inducing larvae to feed on cattle in 

 the laboratory. They concluded that these animals were not 

 suitable as larval hosts but were able to rear R. pravus on 

 rabbits. The original specimens, stage not stated, were found 

 on grass in tsetse-infested areas. 



Recently, Walker (1956) has obtained life cycle data of the 

 three-host type from engorged females maintained at 25°C . to 

 27°C . Larvae and nymphs were kept between 16°C . and 23°C . 

 Under these conditions, the life cycle was a^ follows: 



PERICD DAYS 



Prefeeding periods are not included. 



- 679- 



