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their wings present little resemblance to an ordinary fly. The purely 

 African genus Echestypus, Speiser, the three species of which at 

 present known are parasitic on antelopes, is distinguished from 

 Lipoptena by the absence of ocelli. Melophagus ovinus, which is 

 a European parasite of sheep, has not yet been recorded from any 

 African locality ; there can, however, be little doubt that in South 

 Africa as in North America it has been introduced with its host, 

 and a brief search of the fleeces of any South African flock would 

 probably suffice to reveal it. 



The legs in Hippoboscidae are of moderate length, powerfully 

 developed, and otherwise adapted for clinging to the hair or feathers 

 of the host, the tarsal claws, which are of unusual strength and shape, 

 having a special process (basal plate) at the base, with, in the bird 

 parasites, with the exception of Ornithoica, the addition of a long 

 accessory tooth. 



It is probable that the Hippoboscidae are descended from ancestors 

 belonging to the Muscidse, which underwent modification in bodily 

 structure as a consequence of the adoption of a parasitic mode of 

 life. Whether, as in the case of phlebotomic Muscidse, both sexes 

 suck blood is not yet known. The bites of Hippoboscidae do not 

 seem to be painful, and to hosts accustomed to their presence little 

 annoyance is apparently caused by these flies ; a strange horse or 

 dog however is often greatly worried by a single Hippobosca, owing 

 to the irritation produced by the movement of the fly through the 

 hair. Except for some special reason, as when forced to seek other 

 quarters owing to the death of their host, Hippoboscidae as a rule 

 make little use of their wings, but on occasion their flight is quick and 

 short, and they sometimes settle on and occasionally bite human 

 beings.* 



The mode of reproduction of Hippoboscidae is 

 Life-history, a further development of the process seen in the 



Tsetse-flies. Instead of, like ordinary Diptera, 



* See notes on Hippobosca maculata, Leach. So far as Africa is concerned, 

 no instance has been recorded of a bird-parasite belonging to this family biting man, 

 but the author has been informed by Dr. D. Sharp that in the north of Scotland, 

 according to Mrs. L. Duff Dunbar, of Thulachan, Caithness, a gamekeeper in the 

 employ of the lady mentioned was once severely bitten by Orniihomyia lagopodis, 

 Sharp, from Red Grouse. 



