414 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.68- 



5. Anal angle of the wing prominent, almost square ; Rs very elongate, straight ; 



basal deflection of Cui before the fork of M Antocha (p. 415), 



Anal angle of the wing feeble ; Rs shorter, more arcuated ; basal deflection of 

 Cth. at or beyond fork of M 6. 



6. A'l beyond the tip of Sc long, longer than the sector alone ; veins issuing from 



cell first Mi very long Dicranoptycha (p. 415). 



A'l beyond the tip of Sc short, less than the length of the sector alone; veins 

 issuing from cell first M^ alone TeucJiolabis (p. 416). 



Genus RHAMPHIDIA Meigen. 



KEY TO SPECIBS. 



1. Rostrum short ; legs yellow, the tips of the femora and the tibiae black ; 



wings tipped with dusky R. flavipcs (p. 414). 



Rostrum long ; legs uniformly dark brown ; wings uniformly subhyaline, not 

 tipped with dusky R. mahicnsis (p. 414). 



I'he larvae of these species are semiaquatic in their habits. 



RHAMPHIDIA FLAVIPES Macquart. 

 Plate 23, fig. 3. 



Frequent; season May 19 to August 29; often attracted to light, 

 P. I. 



* RHAMPHIDIA MAINENSIS Alexander. 



Hyattsville, Maryland, September 1. 1912. J. K. Malloch. 

 Genus ELEPHANTOMYIA Osten Sacken. 



ELEPHANTOMYIA WESTWOODI Osten Sacken. 



Several records from Piedmont localities; June 5 to August 23. 

 The curious golden-yellow larva lives beneath the damp bark of 

 fallen trees: here the fiv has been bred from a rotten willow log., 

 P. I. ' 



Genus TOXORHINA I.oew. 



KEY TO SPECIES. 



1. Cell first ih closed ; body coloration brownish yellow ; size larger, wing about 



6.5 mm. (Regional.) T. magyia O.sten Sacken. 



2. Cell first Ih open by the atrophy of m (closed in abnormal specimens only) ; 



body coloration gray; size smaller, wing leas than 5.5 mm 



T. mnliehriH (p. 414). 



TOXORHINA MUUEBRIS Osten Sacken. 



The adult is usually found on flowers; Beltsville, Maryland, Jime 

 14, 1914; July 9, 1916; August 8, 1913, common on flowers of Clethra 

 alnifolia; August 15, 1909, on flowers of Solidago canadensis (the 

 last specimens recorded by Knab as Geranomyia diversa) . McAtee; 

 Great Falls, Virginia, on flowers of Ceanothus. Nathan Banks ; Glen- 

 carlyn to mouth of Four-mile Eun. Virginia, on %wers of Apocy- 

 num medium, June 11. 19\6. McAtee. 



