Ko. 2313. NEW SPECIES OF EOCENE INSECTS— COCKERELL. 



261 



7^/w.— U.S.G.S., 1076. YHiite River, Colorado. (Scudder collec- 

 tion.) 



Holoty pe.—Cht. No. 66572; U.S.N.M. 



This insect is of particular interest, since all the rather numerous 

 Asilidae from Florissant are referable to existing genera. The very 

 long apical petiole of marginal cell, and base of submarginal so near 

 the anterior cross-vein, will at once distinguish it. The dark cloud 

 in the apical part of marginal cell is suggestive of Leptidae, and is 

 not an asilid character. It is possible that if we had the whole fly 

 a distinct family would be indicated, and on the wing alone it seems 

 justifiable to establish a subfamily Asilopsinae. 



Family THEREVIDAE. 



EOTHEREVA, new ger.us. 



Bare rather elongate flies, similar to TJiereva in general appearance, 

 but with very long slender antennae, the second joint somewhat 

 longer than the other two together; third longitudinal vein simple, 

 arched, ending slightly above 



wing-tip, therefore no cubital 

 fork; first longitudinal vein 

 simple and relatively short, 

 as in Therevidae ; a very dis- 

 tinct stigmatic infuse ation, 

 bounded below by the second 

 longitudinal vein ; five posterior cells, the fourth at least contracted, 

 perhaps closed, but indistinct apically; discal cell small and narrow, 

 the anterior cross-vein equally distant from its base and apex; anal 

 <;ell probably open, perhaps widely so, but its lower side can not be 

 made out. 



Type. — EotJiereva simplex, new species. 



EOTHEREVA SIMPLEX, new species. 



Plate 35, fig. 4. 



Length 6 mm., of which 3.4 mm. is abdomen ; wings about 5.5 nam. 

 reddish hyaline, the stigmatic region darker; antennae about 1.5 mm. 

 long, the first joint 240 iu, the second 880 m, the third 560 /x. Anterior 

 cross-vein 480 /x from base and apex of discal cell; end of second longi- 

 tudinal vein to end of third, measured in a straight line, about 1600 ju. 

 Body as preserved pale reddish. 



Type.— U.S.G.S. 21, Roan Mountain, Colorado. (Scudder.) 



Holoiype.—CsiL No. 66573, U.S.N.M. 



Certainly a Therevid, but peculiar for the absence of the cubital 

 fork, about which there is no doubt. The long slender antennae are 

 also distinctive. 



Fig. 7.— Asilopsis fusculus. Part of wing. 



