146 U. S. NATIONAL MUSEUM BULLETIN 209 



6. Penultimate segment of flagellum about 1.9 as long as wide; more than 0.6 of 



the face white; squama narrower and with a stronger median ventral 



protuberance, subspecies of caerulescens 7 



Penultimate segment of flagellum about 1.65 as long as wide; less than 0.4 of 

 the face white; squama broader and with a weaker median ventral pro- 

 tuberance 9 



7. Front and middle femora mostly blackish or brown. 



8a. caerulescens subcorticalis (Walsh) 

 Front and middle femora fulvous 8 



8. Middle and hind coxae entirely blackish or brown. 



8b. caerulescens caerulescens (Dahlbom) 

 Middle and hind coxae about half fulvous, the rest infuscate. 



8c. caerulescens floridanus (Banks) 



9. Clypeus white on each side, black in the middle ... 10. nigrellus (Banks) 

 Clypeus entirely black, subspecies of architectus 10 



10. Wings faintly infuscate; range: Pacific States, British Columbia, Nevada, 



and parts of New Mexico 9a. architectus metallicus (Banks) 



Wings very faintly infuscate; range: Atlantic west to Colorado, and Arizona. 



9b. architectus architectus (Say) 



FEMALES 



1. Pygidial area mat 2 



Pygidial area polished 5 



2. Depressions of pronotum with cross wrinkles; second flagellar segment about 



6.4 as long as wide; forewing 10.7 to 12.0 mm. long; front trochanter 

 entirely fulvous; range: Arizona and Mexico . . . 6. mexicanus (Cresson) 

 Depressions of pronotum smooth, without cross wrinkles; second flagellar 

 segment about 4.8 as long as wide; forewing 6.5 to 9.0 mm. long; front 

 trochanter usually more or less infuscate; range: Atlantic to 100° west 

 longitude, subspecies of mellipes 3 



3. Middle and hind femora and tibiae black; range: eastern North America 



north of 42° latitude 5c. mellipes vai-iitarsatus (Dalla Torre) 



Middle and hind femora and tibiae fulvous 4 



4. Middle and hind coxae entirely blackish; range: eastern United States south 



of 42° latitude, but not including southern Florida. 



5a. mellipes mellipes (Say) 

 Middle and hind coxae largely ferruginous; range: southern Florida. 



5b. mellipes meridianus, new subspecies 



5. Thorax dull black, without iridescence 6 



Thorax dark with a definite bluish or greenish iridescence 9 



6. Coxae black 7 



Coxae fulvous 8 



7. Middle and hind trochanters infuscate; pygidial area with medium sized 



punctures separated by about 1.7 their diameter; wings subhyaline. 



3. variolarum, new species 

 Middle and hind trochanters fulvous; pygidial area with small weak punctures 

 separated by about 5.0 their diameter; wings pale brown. 



2. inermis, new species 



8. Pubescence of head and thorax unusually dense, the setiferous punctures of 



the pleura so close that they are confluent in rows; flagellum light brown, 

 elongate, its second segment about 7.3 as long as wide; wings subhyaline. 



1. flavicoxae (Banks) 



Pubescence of head and thorax not unusually dense, the setiferous punctures 



of the pleura distinct from one another; flagellum blackish, not unusually 



elongate, its second segment about 6.0 as long as wide; wings weakly to 



strongly infuscate 4. adjuoctus (Banks) 



