92 



An^tals of the Teansvaal Museum. 



EE. Shield cordiforin in outline. 



F. Eyes lieniispherical ... Hijaloiniufu 

 ■ , . ... FF. Eyes Hat ... ... AiubJ ijomma. 



L(UT(l. 



(Key based on known Transvaal forms.) 

 A. Body nincli longer than wide; narrowed at both extremities. 



hi'odes, 



A A. Body as long as vride, or longer than wide, but widely 

 rounded behind. 



B. Palpi produced into prominent lateral points. 



Hoemaphysalis^ 



. : BB. Palpi more or less cylindrical. 



(\ Body as wide as long; circular in outline 



Avonomma^ 



C'C. Body longer than wide. 



D. Palpi very short and thick ... Marijfiropus^ 

 DD. Palpi elongate. 



E . Palpi of medium length ; more or less- 

 pointed at tips ; dorsal shield allows a 

 portion of the body to show along its 

 antero-lateral edge ... Rh ipicephalus . 

 FTE . Palpi very long; dorsal shield covers all 

 of anterior portion of body. 

 F. Eyes hemispherical ... HyaJomma, 

 FF. Eyes flat ... ... Amhlyomma^ 



GENITS IXODES, (LATRELLLE.) 



Acarus (ex. p.), Linnaeus (1758). 

 Ivodes, Latreille (1795). 

 Cynorhaestcs (ex. p.), Hermann (1804). 

 Crotofius (ex. p), Dunieril (1822). 

 Ixodes, (Latreille), (Neumann, 1899). 



Eyes absent. Palpi long. Anal groove opened or closed behind^ 

 but tangent to the anus by its anterior concavity. No terminal spurs- 

 on the tarsi. The male with the ventral surface covered with plates, 

 as follows: — One pregenital plate between the sexual opening and 

 the rostrum ; two lateral epimeral plates more or less surrounding 

 the stigmata and coxae ; a genito-anal plate, of elongate pentagonal 

 shape, between the sexual opening and the anus ; an anal plate, 

 triangular, pointed or circular, behind the preceding, the anterior 

 end surrounding the anus, the base formed by the posterior margin 

 of the body; two quadrangular adanal plates, parallel to the anal 

 shield ; dorsal shield leaving a margin more or less wide, uncovered 

 on lateral and posterior margin of body; no posterior festoons. 

 Stigmatic plates oval. F'evude with three longitudinal grooves on the 

 posterior part of the dorsal surface ; on the ventral surface two long 

 genital grooves, extending from the sexual opening, and diverging 

 caudad ; also two small anal grooves united in front of the anus,, 

 parallel or diverging behind, rarely converging. Stigmatic plates, 

 circular. 



