98 



Ai^XALS OF THE TeANSVAAL MuSEUM. 



and lias fifteen to sixteen teeth ; palpi long, rather slender, second 

 article longer than the third. Legs slender, brick red; coxae I, li, 

 and III fiat, unarmed, with posterior margin sharp; coxae IV more 

 swollen, with a small tul)ercle on the external third of the posterior 

 margin ; tarsi elongate, slender. 



Habitat. — Cape Colony. 



Hosts. — Sheep. 



I have seen no specimens of this tick. The description is taken 

 from that of Professor Neumann. It is supposed to transmit a disease 

 of sheep (Neumann). 



^ GENUS HYALOMMA, KOCH. 



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

 Li'odes (ex. p.), Latreille (1796). 

 Cynoi-haestes (ex. p.), Hermann (1804). 

 H yaJonnna , Koch (1844). 

 HyaJo iinua , Koch (Neumann, 1899). 



Eyes present, sometimes hemispherical, shining, in a sub- 

 marginal pit of the shield, sometimes fiat and scarcely salient, 

 nostrum long, with palpi valvate. Anal groove in a semi-circle, 

 opening in front, joining the sexual grooves, and followed by a 

 median ano-nmrginal groove. Body in an elongate oval. Colour 

 brown, more or less intense. Male with ventral face provided with 

 two pairs of plates; two anal plates, triangular, large, and two 

 accessory plates, very small, narrow; often two accessory plates 

 behind the anal plates; stigmatic plates comma-shaped with a 

 long tail. Dorsal shield festooned on its posterior margin. Tarsi 

 spurred. FcmaJe with stigmatic plates triangular; posterior margin 

 of body festooned before repletion. 



Kocli made the distinction ])etween this genus and Am hi jjo ni ma 

 depend on the eyes, hemispherical in Hyalaaniu/ and fiat in 

 Amhlyomma. Neumann found that there were a great many inter- 

 mediate stages between these two types of eyes, but that the presence 

 of anal plates in the male of Hyalomma was an essential character. 

 The females of H yalowwa, so far as known, he found distinct from 

 Amhlyomma hy their orbited eyes and oval shields, instead of 

 triangular or cordiform shields; also the eyes near the niidde of shield 

 instead of near the anterior third or fourth, as in Amhlyomma . This 

 genus has only a few species, two of which occur in South xVfrica, 

 H. acffyptium with its variety impressum and H. hi ppopotamense . 



The variety im /jressum seems to be more abundant than 

 H. aerjyptium in the Transvaal. 



Males. 



A. Dorsal shield shagreeiied ... ... aegyptium impressum . 



AA. Dorsal shield with punctuations unequal but distinct. 



li. Eyes prominent, black, spherical ; punctuations of shield 

 numerous, unequal, coxae I deeply divided 



(legyptium... 



