406 MEDICAL ENTOMOLOGY 



2. Distance of oral border from frontal suture as great as from 



the suture to the vertex * ..-..' , . . . PseudoHersia 

 Distance from oral border to suture distinctly less than from 



the suture to the vertex ...... Olfersia. 



2. SUBFAMILY HIPPO- Hippoboscidae in which the 



wing is well developed and 



. 



the anal cell is absent ; the 

 pronotum is visible from 

 above as a projecting 

 coloured ring ; ocelli are 

 wanting. Genus. Hippo- 

 bosca. 



3. SUBFAMILY ALLO- Hippoboscidae with rudimen- 



tar y wm 8 s in which the 

 ... , , . 



anal vein is so far devel- 

 oped so as to appear retro- 

 flexed and to enclose an 

 anal cell ; ocelli absent. 

 Genus Allobosca. 



4. SUBFAMILY LIPOP- Hippoboscidae some of which 



TPVTNAF have weak wings with re- 



duced veins ; most either 

 with wings shredded or con- 

 sisting of mere tags ; ocelli 

 present or absent. Genera 

 Lipoptena, Echystcpus 

 and Melophagus. 



The two important genera are distinguished as follows : 



1. Wings present, but as a rule becoming detached in the 



female ; ocelli present .... ^ ... Lipoptena. 

 Wings and halteres entirely wanting Melophagus. 



5. SUBFAMILY ORNI- Hippoboscidae with either de- 



THOMYNAE veloped or reduced wings; 



in the former case usually 

 with an anal cell. Ocelli 

 may be present or absent ; 

 those with an anal cell have 

 ocelli ; others again have 

 no distinct venation. Gen- 

 era : Ornithoeca, Orni- 

 thotnyia, Stcnopteryx Or- 

 nithoctona, Ornithopcr- 

 tha, Ornithophila, Cacta- 

 crhina, Myiphthiria Bra- 

 chypteromyia, and Stilbo- 

 mctopa. 



The important genera can be distinguished as follows : 



1 . Claws with an accessory tooth ......... 



Claws simple, without any accessory tooth between the basal 

 . plate and the tip , -- .., -- - *-,- -, . . 



