Gastrophilus. 



81 



pointed tooth and hind femora broad and broadened towards base 

 and here abruptly thinned on ventral side. The legs with white and 

 yellow hairs, on tibiæ also black hairs dorsally; hind femora without 

 long hairs. Wings a httle greyish yellow tinged ; behind medial cross- 

 vein a broad, dark band down to the hind margin, and apex of first 

 posterior cell dark seamed; veins pale yellow; posterior cross-vein 

 placed below medial cross-vein or near it. Squamulæ white, the 

 lower with a fringe of long white hairs. Halteres yellow to brownish. 

 Female. Similar; frons still broader; orbits with mostly black 

 hairs. Scutellum black-haired. Abdomen with yellow and black 



Fig. 11. Wing of G. equi ?. 



hairs, sometimes almost quite black-haired except at base and sides; 

 sixth and seventh segment black; the ovipositor formed of seventh 

 segment, double as long as broad, cleft at end and above, and with 

 a pair of lamellæ at end. Tooth on hind trochanters quite small and 

 hind femora less broad at base and less abruptly thinned. 



Length. Male 11 mm, female 16 mm. 



G. equi is common in Denmark, and the imago not rarely met 

 with where there are horses. 



Geographical distribution: — Nearly cosmopolitic, all Europe, 

 Africa, Asia, North America and Australia. 



3. G. haemorrhoidalis Linn. 



1758. Linn. Syst. Nat. X, 590 {Oestrus). — 1805. Fabr. Syst. Antl. 229, 7 

 {Oestrus). — 1818. Fall. Dipt. Suec. Haemat. 13, 7 {Oestrus). — 1824. Meig. 

 Syst. Beschr. IV, 177, 4 (Gastrus). — 1844. Zett. Dipt. Scand. III, 981, 7 

 {Gastrus). — 1862. Schin. F. A. I, 392. — 1863. Brauer, Mon. Oestr. 83, 6, 

 Tab. I, Fig. 5, Tab. VII, Fig. 4. — 1907. Kat. palåarkt. Dipt. III, 595. 



Male. Frons as broad as the eye. Orbits and frons yellowish, 

 darker at vertex; face yellowish white. Orbits and frons with yellow 

 to brownish, at vertex darker hairs; cheeks and jowls with whitish 



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