GENUS HIPPOBOSCA 407 



2. Ocelli present ,'. . Ornithomyia, 



Ornithopertha and Ornithoctena. 



Ocelli absent . . \ . . . ... . . 5tilbometopa. 



3. Anal cell present . . . ". . . . . . r -'~T~- . -. 4 



Anal cell absent . . . Ornithophila. 



4. Ocelli present ; wings narrow and about ten times as long as 



broad . ., . . . Sternopteryx. 



Ocelli absent ; wings only about three times as long as broad ... 5 



5. Wings about as long, or little longer than the abdomen . . Oxypterum. 

 Wings rudimentary and shorter than the abdomen ..... 6 



6. Wings with distinct veins. Asiatic species .... Myiophthiria. 

 Wings with indistinct veins. North American species . . Brachyteromyia. 



GENUS LYNCHIA, WEYENBERG 



The hippoboscids belonging to this genus are parasitic on birds ; some 

 ten species are recorded from the Mediterranean region, Madagascar, the 

 Ca.no.ry Islands, and South America. Lynchia maura, Bigot, is a com- 

 mon parasite of pigeons, and is found all along the shores of the Med- 

 iterranean and in parts of South America. It was in this fly that the 

 Sergents observed the development of Haemoproteus (Halteridium) 

 columbae, having previously failed to find any development in Citlex 

 pipiens. In Brazil, Beaurepaire Aragao has recorded the development 

 of the halteridium of the pigeon in Lynchia bninea lividocolor. His 

 observations, together with those of the Sergents, strongly suggest that 

 this blood parasite does not pass through a typanosome stage in its in- 

 vertebrate host. 



GENUS HIPPOBOSCA, L. 



Head flattened, both sexes dichoptic. The thorax is nearly always of 

 a yellowish or reddish brown colour, and is marked with spots or bands. 

 Abdomen sac-like and without distinct segments. Wings in the resting 

 position crossed and completely covering the abdomen. 



The flies of this genus are often spoken of as horse flies, a term which 

 is better applied to the Tabanidae. With one exception, Hippobosca 

 struthionis, Jan., all the species are parasitic on mammals. It is some- 

 times difficult to recognize the sexes ; the female always has a small 

 chitinous flap at the dorsal end of the abdomen, while in the male 

 there is a small chitinous spine in the same situation. 



Hippobosca maculata, Leach, (Plate LI I, fig. 1) is common on cattle 

 and horses ; in India it is often seen in large numbers on draught cattle, 

 resting about the scrotum. H. struthionis is found on the ostrich, 



