298 Hominoxious Arthropods 



n. Wing hyaline with smoky median cross band, 



and two or three spots; posterior trochanters 



with hook in the male and a prominence in 



the female. World wide distribution. G. equi. 



nn. Wings without spots. 



o. Posterior crossvein (m-cu) distad of the 

 anterior crossvein (r-m); legs, particularly 

 the femora, blackish brown. Europe and 



North America G. haemorrhoidalis 



oo. Posterior crossvein opposite or proximad of 

 the anterior crossvein. Europe and North 



America G. nasalis 



11. The costal vein ends at the tip of MI 2, Mi+2 with a 

 bend, the cell R& hence much narrowed in the 

 margin, or closed. 



m. Proboscis geniculate, inserted in a deep slit; 



female without extricate ovipositor; arista 



either bare or plumose; squamae large; facial 



grooves approximated below. 



n. Arista bare, short. Larvae in rodents. Tropic 



America. B. princeps Bogeria Austen 



nn. Arista pectinate above. 



o. Tarsi broadened and flattened, hairy, anal 



lobe of the wing large. Larvae in rodents. 



A number of American species. Cuterebra. 



oo. Tarsi slender, not hairy; anal lobe of the 



wing moderate. Larvae in man and other 



mammals. Tropic America. D.cyaniven- 



tris Dermatobia Br. 



mm. Mouth parts very small, vestigial; arista bare. 

 n. Facial grooves approximated below, leaving a 



narrow median depression or groove. 



o. Cell RS closed and petiolate, body nearly 



bare. Larvae in the nasal cavities of the 



smaller Ungulates. The sheep bot fly. 



O. ovis. Widely distributed .. Oestrus L. 



oo. Cell Rs narrowly open, body hairy. Larvae 



parasitic on deer. Europe and America 



Cephenomyia Latr. 



nn. Facial grooves far apart, enclosing between 

 them a broad shield- shaped surf ace; squamae 

 large; female with elongate ovipositor. 



Larvae hypodermatic on Ungulates 



Hypoderma Clark 



o. Palpi wanting; tibiae thickened in the middle. 



p. Hair at apex of the abdomen yellow; legs 



including femora yellowish brown .... 



. H. diana 



