Misformed specimens of R. e. evert si have been reported on by- 

 Santos Dias (l947B,194.aA,193^. An egg toxin has been fooind in 

 this species (De Meillon 19/i2) . Symbiotes have been reported and 

 disctissed by several workers: Cowdry (1923,19250,1927), Buchner 

 (1926), and Jaschke (1932). The arch of the eye has been briefly 

 mentioned by Gossel (1935). Donitz (1905) observed copulation _ 

 by insertion of the male hypos tome into the female genital aperture 

 while the legs are used as clasping organs adjacent to the cor- 

 responding legs of the female _ but was unable to ascertain how 

 seminal fluid was passed; Christophers (1906) stated that ob- 

 viously it is accomplished by transfer of spermatophores during 

 the mating act. 



The life cycle and morphology of the red tick are so peciiliar 

 within this genus that a special subgeneric niche might seem in- 

 dicated for R. evert si . ^Theiler informs me (correspondence) 

 that Dr. CooTey also entertained this idea while he was in South 

 Africa, but that the immature stages are so normally rhipicephalid 

 as to dampen any urge to take this step 7« 



DISEASE RELATIONS 



MAN ; Boutonneuse fever (Rickettsia conorii ). 



CATTLE ; East Coast fever (Theileria parva ) . Pseudo-east 

 coast fever (T. rautans). Redwater (Babesia bigemina ). Spiro- 

 chetosis (Borrelia theileri ). Not a vector of heartwater (Rickett - 

 sia ruminantium j . A secondary bacterial infection by Corynebacterium 

 pyogenes causes an otitis leading to the sloughing of the host's 

 external ear when infested by larvae and nymphs. The virus of "a 

 specific transmissible petechial fever of cattle" may be trans- 

 mitted to sheep by the red tick. 



SHEEP ; Lamb paralysis (? toxin). Apparently not a vector of 

 Nairobi sheep disease (virus). See paragraph above. 



HORSES , MULES , and DONKEYS ; Equine piroplasmosis (biliary 

 fevers J (Babesia eqxii and B. caballi ). Spirochetosis (Borrelia 

 theileri). 



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