56 Families and Genera of 



joints very short, the third round or oval, with a dorsal arista. 

 Mouth opening small, the mouth parts small or rudimentary. Eyes 

 comparatively small, bare. Ocelli present. Abdomen never elon- 

 gate ; hypopygium concealed ; ovipositor often projecting. Legs 

 moderately strong, tlie hind pair sometimes elongate. Tegulae usu- 

 ally large, concealing the halteres ; sometimes small, and long 

 ciliate. Wings usually with fine transverse wrinkles ; third vein 

 simple; first posterior cell fully or narrowly open, or closed and 

 petiolate ; basal cells small ; discal cell sometimes wanting ; the 

 posterior part of the wings broadly unsupported by veins. 



Bot flies, parasitic in the larval stage in the skin, stomach, frontal 

 or pharyngeal cavities of perrisodactyls, artiodactyls, rodents, ele- 

 Xibant, monkeys, etc. Each species is parasitic in the same way, 

 and, as a rule, on the same species of mammal ; and allied species 

 usually have similar habits, on allied animals. The occurrence of 

 bot-fiies on other than mammals needs verification. Pupal stage 

 passed in the ground. 



1. First posterior cell wide open, the fourth vein running straight 



to the border of the wing. (Horses.) . Gastrophilus 



First posterior cell narrowed or closed, the fourth vein distinctly 



bent forward 2 



2. First posterior cell closed and petiolate. (Sheep.) . Oestiu'.s 

 First posterior cell narrowly open. ..... o 



8. Arista plumose on the upper side. (Rodents.) . Cutekebra 



Arista bare ; pilose species. ....... i 



i. Subantennal grooves separated by a median ridge, terminating in 

 a shield-shape surface below, limited on each side by a slen- 

 der groove running to the oral margin. .... 5 



Subantennal grooves continuous to the oral margin, feebly sepa- 

 rated from each other. (Deer.) . . Cephenomyia 



5. Palpi present. (Reindeer.) Oedemagena 



Palpi wanting. (Oxen, etc.) .... Hypoderma 



Gastrophilus Leach, 1817. 

 Hypoderma Clark, Essay on Bots, 1815. 

 Oedemagena Latreille, Fam. Nat. 1825. 

 Oestrus Linne, Fauna Succica, 1761. 

 Cephenomyia Latreille, Fam. Nat. 1825. 

 Cuterebra Clark, Essay on Bots, 1815. 



