150 Mr. F. Walker's Characters of undescribed Diptera 



Genus Dolichopus, Latr. 



Of this genus Mr. Saunders's collection contains a few appa- 

 rently undescribed North American species, but it is difficult to 

 ascertain their characters on account of the manner in which they 

 are set. 



Fam. 11. LONCHOPTERIDiE. 



Fam. 12. PLATYPEZIDiE. 



The European species of these families may amount to about 

 thirty. No exotic species have yet been discovered. 



Fam. 13. PIPUNCULID^. 



About twenty European species. One from North America 

 has been described, and another occurs in Australia. 



Genus Pipunculus, Latr. 

 Pipunculus translatus. 



Mas, — Niger, nitens, capite antico argenteo, genubus tarsisque, 



alis limpidis, venis nigris. 

 Male. Black, shining ; head silvery in front ; knees and tarsi 

 tawny ; wings limpid, veins black. 



Length of the body 1^ line ; of the wings 2 lines, 

 United States. 



Fam. 14. SYRPHID^. 



The species of SyrphidcE may be about 1000 in number, and as 

 a synopsis of all the genera would be unsuitable here, a list of 

 those which do not occur in Europe is subjoined : — 



NORTH AMERICA. 



Chymophila, Serville ; Ceratophya, Wied. ; Sphecomyia, Latr. ; 

 Mixtemyia, Macq, ; Plagiocera, Macq. ; Imatisma, Macq. ; Ocy^ 

 ptamus, Macq. ; Somula, Macq. ; Polydonta, Macq. 



SOUTH AMERICA. 



M'txogaster, Macq. ; DoUchogyna, Macq. ; Senogaster, Macq. ; 

 Copestyhim, Macq. 



