^XII] H^MOPROTEUS COLUMB^ 379 



the rest of the surface by a distinct groove. The anterior end 

 is surrounded by a darker hne, marking the line of dehiscence 

 of the cephalic cap. There is a longitudinal row of six punc- 

 tures on each side, above and below, near the lateral margin. 



Hippohosca and disease. In addition to being the carrier 

 of Trypanosoma theileri {vide infra), Mr Hutcheon states that 

 a local form of anthrax, which is very common in horses in 

 parts of Griqualand West, is most probably due to infection 

 caused by Hippohosca rufipes. There is no experimental 

 evidence in support of this statement. 



Hippohosca maculata, Leach, also occurs parasitic on horses 

 and cattle in many parts of the world, including South Africa, 

 where, however, it is comparatively uncommon. It is probable 

 that this species as well as rufipes is capable of transmitting 

 T. theileri, and in his experiments Theiler used a mixture of 

 the two. As, however, rufipes is the more common species in 

 South Africa, where T. theileri is especially prevalent, it is 

 only reasonable to assume that it is the usual carrier of the 

 infection. 



CHAPTER XXIII 



INFECTIONS TRANSMITTED BY HIPPOBOSCIDAE 



I. Hsemoproteus columbs Celli and San Felice, 1891. 



General account. Hcemoproteus coliimbcE, the halteridium 

 of the pigeon, is very common in many parts of the world, 

 having been recorded from Italy, France, North Africa, India 

 and Brazil. It is apparently non-pathogenic, for pigeons may 

 shew large numbers of the parasites in the blood circulation 

 for years, without any obvious harmful effects being produced. 

 Et. and Ed. Sergent, in 1906, shewed that in Algeria the para- 

 site is transmitted by Lynchia maura Bigot, one of the 

 Hippoboscidse. In 1908, Aragao worked out the life-cycle of 

 the parasite both in the blood of the pigeon and in the inver- 

 tebrate hosts of this infection in Brazil, viz., Lynchia hrunea 

 and L. lividicolor (Oliv.). Aragao's account is somewhat 



