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Hope, is known to occur in Egypt, the Anglo-Egyptian Sudan, and 

 the East Africa Protectorate ; it is parasitic on dogs, and is found 

 from South Europe to North China and Japan. Hippobosca 

 camelina, Leach (syn. H. dromedarina, Speiser), the sixth and 

 largest species, as its name implies infests camels, and its distribution 

 is doubtless co-extensive with that of its host ; at any rate in Africa 

 it is known to occur from Somaliland along the North-Eastern and 

 Northern African littoral at least as far as Algeria, and a specimen 

 has even been received from Northern Nigeria, taken in the district 

 east of Illela, in 1904 (Captain P. S. Lelean, R.A.M.C.). In addition 

 to African examples of H. camelina, others have been received from 

 Arabia, Sinai, Syria, Asia Minor, and Southern Afghanistan. 



In the case of species parasitic upon horses and cattle, the flies 

 congregate chiefly on parts where the skin is thinnest, i.e., beneath 

 the tail, on the perinaeum, and on the inner surface of the thighs. 

 The bite does not appear to cause pain, and horses have been seen 

 standing perfectly quietly with as many as twenty or thirty 

 Hippobosca maculata crawling between their thighs, in addition to 

 other specimens which had the proboscis buried in the skin ; on 

 the other hand sensitive horses are sometimes driven almost frantic 

 by the irritation caused by a single one of these flies crawling over 

 them. The toothed claws enable the fly to cling so tightly to the 

 hair that it is impossible for an animal to dislodge it by a brush from 

 its tail, and the quick and somewhat crab-like movements of the 

 insect, which when disturbed usually runs sideways, tickle the host 

 and are exceedingly irritating to a nervous animal. 



Reproduction in the genus Hippobosca is of the 

 Life-history, normal Hippoboscid type, the female producing 



but a single adult larva at a birth, and the larva 

 being retained until mature within the uterus or dilated oviduct, 

 where it is nourished by the secretion of a pair of much ramified 

 glands. On extrusion the larva is a white or pale yellowish, ovoid 

 or flattened globular body, with a small depression at the oral 

 pole and a conspicuous black cap at the opposite one, but without 

 showing any ordinary traces of segmentation. On the dorsal and 

 ventral surfaces, however, a longitudinal row of six punctures on 



