OF PHILADELPHIA. 365 



OCYPTERA Fabr. 



0. ARCUATA. — "Wings blackish on tbe costal margin ; apical 

 cross-nervure arquated at its origin. [174] 



Inhabits Indiana. 



Body blackish : hypostoma yellowish-white ; orbits, excepting 

 behind and on the vertex, honey-yellow with a gray reflection : 

 front with a dilated blackish vitta : antennae with the base of the 

 third joint obsoletely honey-yellow beneath : thorax with yellow 

 hair before the wings : wings hyaline : costal margin blackish ; 

 terminal cross-nervure not angulated at its origin : halteres yel- 

 lowish : wing-scales white : feet black ; base of the thighs and 

 coxae yellowish : tergum pale yellowish ; basal segment with the 

 base and dorsal line black ; second segment with a large black 

 triangle ; third segment with a gray reflection each side ; re- 

 maining part black : venter pale yellowish, at tip black. 



Length three-tenths of an inch. 



This may readily be distinguished from other species, by the 

 form of the apical cross-nervure. 



MILTOGRAMMA Meig. 



M. TRIPASCIATA. — Tergum black, fasciate with gray. 



Inhabits Indiana. 



Hypostoma and posterior and inferiox orbits honey-yellow, with 

 a silvery reflection : antennae honey-yellow ; seta with dense 

 short hairs : frontal vitta of equal breadth : thorax gray, with 

 many obsolete abbreviated blackish lines : scutel gray : tergum 

 black j segments, except the basal, silvery-gray [175] on the 

 basal half : venter the same : feet black ; thighs on the exterior 

 side with a gray reflection ; wings tinged with brownish. 



Length less than half an inch. 



GONIA Meig. 



G. FRONTOSA. — Front very prominent, abdominal segments 

 whitish at base. 

 ' Inhabits Upper Missouri. 



Body black, with rigid hairs : head pale yellowish-white, seri- 

 ceous : front very prominent, gibbous : eyes placed very far back, 

 oblong-oval, chestnut-brown : stemmata black : antennae black- 

 1829.] 



