90 



Ankals of the Tkaj^svaal Museum. 



longest ; witli six (8) articles, tlie third and tlie tarsi presenting- a false 

 articulatiju near tlie proximal end, except in tlie tarsi of the first pair, 

 where it is near the distal end ; tarsi provided with a cnp-like 

 ainbiilacre, produced from a caruncle, folded more or less fan- like on 

 the ventral surface of the claws. 1 ntegioneni coriaceous, extensible, 

 reinforced by a dorsal shield, eiiiarginated to receive the base of 

 the rostrum, often ornamented with designs and bright 

 colour, grooved in front by two longitudinal grooves (cervical grooves), 

 starting from the angles of emargiiiation at base of rostrum. 

 Stiginatic plates situated behind the coxae of the fourth pair of legs. 

 Sexual opening median transverse, placed more or less in front, 

 between the coxae of the first three pair of legs ; from the commissures 

 of that orifice start two grooves (sexual grooves), which extend back- 

 wards and diverge more or less, terminating at a variable distance 

 from the posterior margin. Sexual dimorphism very marked; the 

 male is ordinarily smaller than the female, more fiattened and often 

 of a less regular oval contour ; the anterior extremity being much 

 more narrow than the posterior ; the dorsal shield covers all the body 

 or leaves uncovered only a marginal band ; the posterior border is 

 usually divided into eleven quadrangular festoons, extending between 

 the dorsal extremities of the two stigiiiatic plates, and often prolonged 

 on to the ventral surface ; the ventral surface often presents shields 

 and plates, the iium])er and form of which are variable. The female 

 is flat at first, but from the development of the enormous quantity of 

 eg^gs, can become of a considerable volume by the extension of its 

 integument in the three dimensions ; the dorsal shield is limited to the 

 anterior part and preserves its original dimensions during distention 

 of the body ; the posterior portion of the abdomen often presents (in 

 the young) eleven festoons. The dorsal surface of the base of the 

 rostrum has Iavo symmetrical pits (porose areas), with very fine 

 punctuations, which are lacking in males, nymphs, and larvae. 



This sub-family is divided into three tribes — the Lrodeae, 

 Rhipicephaleae, and the Amhlyomeae. 



Lrodeae. — Males clothed on all their ventral surface with shields. 

 Anal furrow of both sexes passing around anus in front, and separate 

 from the genital furrows; no eyes. Rostrum elongate. , Includes the 

 genus Ixodes. 



RhipieepJialeae. — Alales provided with one pair of anal shields, 

 ordinarily accompanied by accessory shields. Anal furrow of both 

 sexes passing around the anus behind, and usually joining the genital 

 furrows in front. Eyes present. Rostrum sometimes long and some- 

 times short. Includes the genera lihipieephahis, lUargaropus , and 

 Hyal omnia. 



Amhlyomeae . — Males without anal shields. The anal furrow 

 surrounding the anus behind and usually joining the genital furrows 

 in front. Sometimes with eyes. Rostrum long or short. Includes 

 the genera Amhlyomnia, Aponommo , Neumaniella, lihipieentor, 

 Dermacentor , and Haem aph y sal Is . 



The various genera of this sub-family may be separated by the 

 following key : — 



Adults. 



A. Males clothed on all their ventral surface with shields; anal 

 furrow of both sexes passing around anus in front, and not 

 joined to the genital furrows ... ... (Ixodeae), Ixodes. 



