382 U. S. NATIONAL MUSEUM BULLETIN 216 



This species is transcontinental in the Transition and Upper Austral 

 zones. Most adults occur in June and July but some occur earlier or 

 later. 



3. Poemenia americana (Cresson) 



Male: Front wing 4.4 to 6.4 mm. long; punctures on head and body 

 fine; hind ocellus separated from eye by about 1.2 its long diameter; 

 flagellum with 29 or 30 segments, with rather short, broadly elliptic 

 tyloids on segments 6 to 8; areolet present; first tergite 1.95 to 2.7 as 

 long as wide; first sternite about 0.55 as long as its tergite. 



Coloration as described under the two subspecies, below. 



Female: Front wing 4 to 7.5 mm. long; lateral ocelli separated from 

 each other by 1.0 to 1.1 their diameter, separated from eye by 1.1 to 

 1.25 their diameter; face densely punctate, the punctures separated 

 by about 0.5 their diameter; vertex somewhat mat; temple scabrous 

 from top of eye down 0.5 the distance to mandible; flagellum with 27 

 to 31 segments; pronotal trough with cross ridges; mesoscutum densely 

 punctate, the punctures separated by about 0.5 their diameter; pro- 

 podeum rugoso-punctate, with a weak median longitudinal furrow; 

 areolet present; first sternite about 0.60 as long as its tergite; first 

 tergite 1.65 to 2.1 as long as wide; second tergite 0.93 to 1.95 as long 

 as wide; abdominal segments 2 to 5 with two pairs of ventral scleromes, 

 the front pair of each segment about half as long as the hind pair; 

 first tergite rugoso-punctate, the following tergites gradually less 

 densely punctate, the punctures on sixth tergite separated by about 

 twice their diameter; thyridia circular; ovipositor sheath about 0.55 

 as long as front wing. 



There are two subspecies separable on color, as indicated below. 



MALES 



1. Base of hind tibia dark brownish; hind femur fulvous below and on extreme 

 apex, the rest brownish fulvous; apex of hind coxa fulvous; range: Canada 

 and western United States . . . 3a. americana nebulosa, new subspecies 

 Base of hind tibia whitish; femur whitish below and on extreme apex, the rest 

 brown; apex of hind coxa whitish; range: northeastern United States and 

 adjacent Canada 3b. americana americana (Cresson) 



FEMALES 



1. Pronotum without a well-developed whitish stripe along its anteroventral 

 margin; hind tibia entirely fuscous; middle coxa fulvous, its extreme apex 

 paler; range: Canada and western United States. 



3a. americana nebulosa, new subspecies 

 Pronotum with a broad whitish stripe along its anteroventral margin; hind 

 tibia fuscous, stramineous at base; middle coxa fulvous, its apical 0.3 ± 

 whitish; range: northeastern United States and adjacent Canada 



3b. americana americana (Cresson) 



