HIPPOCENTRUM 



819 



life-history of the tropical species is but little known, but Neave 

 thinks that the majority of the species may have two broods. The 

 life-history of H. phivialis Linnaeus is partially known. The egg 

 stage has not, so far as v/e know, been observed. The larva and 

 pupa are of the Tabanid type, as described above. With regard 

 to pathogenicity, Balfour reports El Takasha (' the attacking fly '), 

 probably H. taciturna Austen, is believed to cause swelling of the 

 lungs in sheep and goats. 



With regard to individual species, H. pluvialis Linnaeus is common 

 in Europe, while H. grahami Austen, 1912; H. daveyi Austen, 1912; 

 H. mbens Austen, 1912 ; H. beringeri Austen, 1912 ; H. crudelis Austen, 

 1912; are some new species recently described by Austen from 

 tropical Africa. Other species are H. obscura Loew, 1875, in South 

 Africa; H. vittata Loew in tropical Africa; and H. bullatifrom 

 Austen in Northern Nigeria. 



Hippocentrum Austen, 1908. 



This genus is nearly allied to Hcematopota Meigen, 1803, but is, 

 according to Austen, distinguished by the fact that the head is 

 for the most part shining, the antennae extremely slender, and the 

 first joint elongate (Fig. 408, k, k'), and the terminal joint of the 

 palpi in the female very large and shining on the outer side, which 

 is strongly convex, while the inner side is flattened; the wings are 

 more or less suffused with dark colour, interrupted with pale streaks 

 or blotches without the peculiar light markings of Hcematopota. 



Species. — H. versicolor Austen, 1908, in Uganda and the Lado, 

 H. trimaculatum Newstead in West Africa, H. strigipennis Karsch, 

 which may be identical with H. trimaculatum, has only been found 

 in Gaboon, and H . murphyi Austen, 1912, in West Africa. The 

 females bite man and animals. The life-history is unknown. 



Tabanus Linnaeus, 1761. 



There are over 900 known species of Tabanus, of which Tabanus 

 bovinus Linnaeus, 1761, is found in Europe, Asia, and South Africa. 

 In the Sudan these flies are called serut-flies: T .diiceniatus Macquart, 

 T.gratus Loew, T. tceniola'Psilisotde'Bea.uvois, T.fasciatus Fabricius, 

 r. africanus Gray, may be noted. In West Africa they are known 

 as mangrove flies. Recently Patton has described the life-cycle 

 of a Crithidia (C. tabani Patton, 1909), which is a true parasite of 

 r. hilarius and another species. 



Subgenus Therioplectes Zeller, 1842. 



A number of species of this genus are known in Europe. Therioplectes 

 micans Meigen, T. borealis Meigen, T. montanus Meigen, and T. tropicus, may 

 be mentioned. 



Subgenus Atylotus Osten Sacken, 1876. 

 Atylotus fulvus Meigen 4 . rusHcus F^bbricius are met with iu Europe, 



