1. H^EMATOPOTA 329 



Abdomen as narrow as the thorax but much longer, almost parallel -sided and 

 rather flat ; dark colored in the British species, and often with grey spots, flecks, or a 

 dorsal stripe, or even (in the male) with ferruginous lateral markings near the base. 

 Genitalia inconspicuous. 



Legs simple but strong ; front coxa3 long ; front femora bare beneath but 

 inconspicuously so because the bare part is of the same grey hue as the rest and is 

 not margined with tiny bristles ; front and hind tibia? without any apical spurs, 

 but the middle pair with two spurs ; front tibial and tarsi with " touch-hairs '' 

 beneath in both sexes. 



Wings (fig. 222) mottled grey and hyaline, with somewhat band-like hyahne spots 

 or incomplete ocelli, in repose lying roof -like over the abdomen. Venation of the 

 normal type of the Tahanicke, but the upper branch of the cubital fork always with 

 a short recurrent veinlet near its base ; all the posterior cells wide open. Siiuamaj 

 moderately large, the alar pair extending about half-way across the thoracal when 

 they are against each other • thoracal pair outspread and in no way covering the 

 halteres ; and both pairs with distinct margins which bear short fringes which are 

 inconspicuous except for the usual Tabanidous tuft of long hairs at the angle. 



This genus is easily distinguished by its peculiarly mottled wings, its 

 comparatively simple antennse, and its comparatively small size, but the 

 species are exceedingly difficult to separate ; in my Presidential Address 

 to the Entomological Society in 1900, 1 said, "It is an exceedingly difficult 

 '■ thing to name a British or European species of Hccmato^wta, because we 

 " meet with them in hundreds, though only in three or four species, but it 

 " is easy to name a South-African Hwmatopota, because we have so few 

 " specimens for examination that almost each specimen can be clearly 

 " distinguished from the others. I prophesy that when we have hundreds 

 " of specimens of North- African, Mid-African, and South-African Hcema- 

 " topota, we shall be infinitely less certain about the nomenclature than 

 " we are now. It is only by the accumulation and examination of long 

 " series of specimens that difficult groups of species can be effectually 

 " dealt with." 



The metamorphoses are I believe but very little known, which seems 

 to be strange for such very common flies. Brauer once bred up a larva 

 from the body of the larva of ffelojjs lanipcs (Coleopt.) through whose skin 

 it had evidently bored, and Ferris (Ann. Soc. Ent. Fr. (4), x., 196, 1870) 

 described the metamorphoses in detail but still remained uncertain as to 

 its habits. 



Hwmatopota is represented by about half a dozen recognised species in 

 Europe and by one or two in North America, while apparently numerous 

 species occur in South Asia and in Africa. The flies are common at a 

 distance from human habitations (especially in the neighborhood of 

 cattle) and the females are most persistent blood-suckers of both man 

 and beast, especially on hot days. The bite of the female may have very 

 different effects upon individuals ; to me it is always a seven days' matter, 

 as if I am bitten on a Sunday I feel merely a sharp needle-puncture 

 (which usually causes a squashed fly ! ), and then I do not feel the 

 slightest further effect until on Monday a very slight irritation can be 

 noticed at the spot of the Ijite, on Tuesday the spot becomes irritable, 

 and on Wednesday it swells up and becomes troublesome, while on 

 Thursday it reaches its maximum in size and irritability, then on Friday 

 it rapidly diminishes, and is only just sensitive on Saturday, after which 

 no further effects are felt. The males sometimes dance in hot sunshine 

 between eleven and twelve o'clock, in groups of from six to nine 



