274 J. M. ALDRICH. 



15. Inner claw of male fore tarsus enlarjied and bent so as to form a small hold- 



ing organ iW. I., Mes.)- -I'dastoiieiirus ungiiiciilatus Aid. 

 Claw not so modified 16. 



16. Orbital cilia pale below 26. 



Orbital cilia black 17. 



17. Tips of hind femora iufuscated above 18. 



Tips of hind femora not infuscated ... 21. 



18. Dorsum of abdomen deep violet in color; large species (Cal., Ariz., S. D.). 



Pelastoueuriis c-yanens Wheeler. 

 Dorsum of abdomen not violet 19. 



19. Dorsum of thorax violet (N. Y., Mass., Fla.). 



I*elasi»tuiieiiriis lRinellatii!x Loew. 

 Dorsum of thorax not violet (N. Y., CJal., Fla.). 



Pelasloiieiirus longieaiKla Loew. 



20. Fore coxae black (N. Y.). Pelao»loneurus abbreviatus Loew. 



Fore coxae yellow, except at base (N. Y., 111., Mex.). 



Pelastoneiirus lusubris Loew. 



21. Hypopygium short, the lamellae divided, forming four long filaments (Kans., 



S. D.) I'elastoneiirus kaii^^eusis Aldrich. 



Uypopygium of different structure 22. 



22. Dorsum of thorax opaque brown, with two fine grey lines; white spots ab- 



sent from transverse suture (N. Y., 111., Mex.). 



Pelasfoiieurus lugiibris Loew. 

 Dorsum more or less shining, the white spots distinct 23. 



23. Fa(;e of male in narrowest place not one-tenth the width of the head (Mex.). 



!§»arcioii US flavicoxa Aldrich. 

 Face of male much wider 24. 



24. Face of male brown, lamellae forked (Tex.). 



Pela.stoneiiriis furcifer Loew. 

 Face of male brown, lamelUe not foiked (La.). 



PelaiStoiieurus proximiis n. sp. 

 Face of male white or whitish 25. 



25. Thoracic dorsum deep violet in coloi' (Fla., Ga., La., D. C). 



Pelastoiieui'iis iH'tus Loew. 

 Dorsum only a little violet behind ; hy]iopygium slender, lamelUe small, oval 



(La.) Pelastoiieiirus parvus u. sp. 



Dorsum only a little violet behind ; hyi>opygiuni thickened, the tip of the 

 black lamella drawn out into a long, curved, black process (Quebec). 

 Pelastoiieurus falcalus n. sp. 



26. Face of male with a brown stripe in middle, sides greyish white (Middle 



States, Mex. I'elasiloneui'us cognatus Loew. 



Face of male not so marked 27. 



27. Lamallae of hypopygium triangular, the upper basal angle prolonged in a 



long filament, projecting outwards or backwards 28. 



Lamellae of different structure 29. 



28. Color bright green ; arista phmiose (W. I., Mex.). 



PelastontMirus argeiiUler Aldrich. 

 Color bright green ; arista pubescent (W. I., Mex.). 



Paraclius fliifer Aldrich. 

 Color bronze-green (Mass.) Paraclius vieinuN n. sp. 



