﻿90 PROCEEDINGS OF THE NATIONAL MUSEUM vol. lOo 



Hind tibia distinctly more infuscate than hind femur and tarsus; front and 

 middle second trochanters and extreme bases of front and middle femora 

 piceous; front and middle coxae and trochanters of male piceous; anterior 

 dorsolateral corners of mesoscutum rounded; ovipositor sheath about 1.6 

 as long as forewing 21. minor Cresson 



8. Front margin of pronotum with a forward-projecting, triangular tooth just 



above its midlength 9 



Front margin of pronotum without a distinct tooth near its midlength (but 

 sometimes with an indistinct tooth near top) 11 



9. Upper face of hind coxa smooth, without cross wrinkles; tarsal claws each 



with three teeth; hind femur black, tibiae and front and middle femora 



yellow; occipital carina a narrow rim 10. flavicrurus Bradley 



Upper face of hind coxa with cross wrinkles; tarsal claws each with four teeth; 

 all femora and tibiae approximately concolorous; occipital carina produced 

 as a flange, somewhat reflexed 10 



10. Third tergite ferruginous; wing spot below stigma large, entering base of 



radial cell (fig. 15, c); legs black; occipital carina a flange that is about 0.8 

 as wide as first flagellar segment (fig. 15, I); British Columbia, Oregon, and 



California 4. montanus Cresson 



Third tergite black; wing spot below stigma usually small so as not to enter 

 base of radial cell (fig. 15, d, or in some males the spot obsolete); legs 

 beyond trochanters fulvous to black; occipital carina a flange about 0.4 as 

 wide as first flagellar segment; Atlantic west to Manitoba and Colorado. 



5. ater Westwood 



11. Upper side of hind coxa smooth, without cross wrinkles; propleurum without 



distinct punctures 12 



Upper side of hind coxa with more or less distinct cross WTinkles; propleurum 

 with weak to strong punctures 16 



12. Wings hyaline (except for spots, fig. 15, h) ; hind femur black; head and thorax 



black; punctures on frons well separated; east of Rocky Mountains. 



14. strangaliae Rohwer 



Wings suffused with reddish brown (except for spots, fig. 15, i); hind femur 



ferruginous, rarely black; head and thorax usually more or less ferruginous, 



but often entirely black; punctures on frons close, somewhat confluent; 



Rocky Mountains and westward 13 



13. Temples, as seen from above, curved inward from directly behind the eye 



(fig. 16, j) ; head, as seen from above, about 0.80 as long as wide; lateral lobe 

 of mesoscutum mostly smooth and polished; top of female head ferruginous, 

 with an oblique blackish triangle projecting upward and backward from 

 eye toward lateral ocellus (fig. 16, j) ; thorax of male marked with ferrugi- 

 nous, at least with a ferruginous mark on side of median lobe of mesoscu- 

 tum 17. fosleei, new species 



Temple, as seen from above, prolonged a little behind eye before curving in- 

 ward (fig. 16, t); head, as seen from above, about 0.75 as long as wide; 

 lateral lobe of mesoscutum mostly weakly wrinkled; top of female head 

 ferruginous or partly or cntirelj' black, but without an oblique blackish 

 triangle projecting inward and backward from eye toward lateral ocellus; 

 thorax of male of A. occidentalis entirelj"^ black, of A. melleus marked with 

 fulvous 14 



14. Ovipositor sheath about 2.0 as long as forewing; top of head rather shining; 



thorax of male marked with fulvous 16. melleus Cresson 



Ovipositor sheath about 1.2 as long as forewing; top of head rather dull; 

 thorax of male entirely black 15 



