562 TERTIARY INSECTS OF NORTH AMERICA. 



vein should curve, brace-like ~-~~~ to meet it, while the third longitudinal 

 vein, from which the cross-vein parts at a right angle, runs in a straight 

 course, as represented. The brace-like direction of the fourth longitudinal 

 vein causes the discal cell to be of equal breadth in the distal half and 

 about twice as broad as the proximal half, the whole cell being unusually 

 long and narrow or fully five times as long as its greatest breadth. The 

 first longitudinal vein reaches the margin nearer the tip of the second lon- 

 gitudinal than the auxiliary vein. 



Length of headless body, 5 mm ; of wing, 4 mm . 



Green River, Wyoming. One specimen, No. 59 (Prof. Leslie A. Lee). 



SYRPHID.-E sp. 

 PI. 10, Fig. 9. 



Another species of Syrphidae appears to be represented in PI. 10, Fig. 

 9, but it is too obscure for determination and is incompletely drawn on the 

 plate. It is in any case a very small species. The basal cells appear to 

 'be long, extending nearly to the middle of the wing; the third longitudinal 

 vein is certainly simple, and there are no intercalaries. 



Green River, Wyoming. One specimen, No. 98 (Prof. L. A. Lee). 



Braner. 

 BRACHYCERA Zetterstedt. 

 Family DOLICHOPODID^E Loew. 



DOLICHOPUS Latreille. 



DOLICHOPUS Sp. 

 Dolichopus sp. Scudd., Bull. U. S. Geol. Geogr. Surv. Torr., IV, 706 (1878). 



A specimen and its reverse are to be referred to this family by the 

 structure of the abdomen and by the general aspect. The wings and head, 

 however, are lacking. The thorax is globose, well arched, and, like the 

 abdomen, of a light brown color, and ornamented with scattered, bristly, 

 black hairs. The tip of the abdomen is recurved beneath. 



The length of the fragment is 3.65 mm . 



Green River, Wyoming. One specimen, Nos. 4124 and 4148 (S. H. 

 Scudder), 



