606 MEDICAL ENTOMOLOGY 



off; the adult attacks a second host. Evertsi is a general feeder, but 

 whatever its host may be, the ticks always remain attached until the 

 replete nymphal stage is reached. Rhipicephalus bursa, the sheep tick, 

 behaves in the same way as evertsi, the larva remaining attached to the 

 first host until the nymph becomes replete. Rhipicephalus appendicula- 

 tus, the common cattle tick of South Africa, will attack almost any warm- 

 blooded animal in all its stages. R. simits and R. capensis, on the other 

 hand, are peculiar. Their larvae appear to feed on some special host ; 

 the nymphs and adults are general feeders. 



GENUS MARGAROPUS, KARSCH 



Capitulum short, with base hexagonal on the dorsal surface, forming on 

 each side a projecting angle. Palps short and broad. Spiracles circular 

 or short ovals ; tarsi with one or two spurs. Anal groove absent ; posterior 

 festoons wanting but in their places there are often small notches. 

 Marginal grooves absent. Scutum chestnut brown, small and in the 

 female with parallel sides in its anterior half. (Neumann) 



The genus Margaropus of Neumann includes Margaropus, Karsch, 

 and Boophilus, Curtice. Nuttall and Warburton retain the genus Boophi- 

 lus and make annulatus the type species. Neumann regards Margaropus 

 winthemi, Karsch, from Valparaiso, as an abnormal specimen of annula- 

 tus; on the other hand Donitz, and Nuttall and Warburton, consider it to 

 be a good species. Boophilus only differs from Margaropus in having 

 bifid coxae and legs of normal width. Neumann gives the following key 

 to the species of Margaropus : 



NEUMANN'S KEY TO THE SPECIES OF MARGAROPUS. 



MALES 



1. Four adanal plates, free anterior to the anus ; segments of the 



legs sub-cylindrical, angles at the joints slightly prominent, annulatus. 



2. Two adanal plates united anterior to the anus ; segments of 



the legs greatly dilated, angles at the joints pronounced . lounsburyi 



FEMALES 



1. Segments of legs sub-cylindrical, spur short, hooks terminal ; 



second and third segments of palps thickest in the middle, 



and forming a sharp angle externally annulatus, 



2. Segments of legs dilated at their distal extremities, spur very 



long, hooks inserted on the dorsal border of the spur, and 

 far from its point ; palps with second and third segments 

 rounded externally .._ .....;, ,..' L-; ;.... e-i^ I. >. lounsburyl. 



