VM) OENKRA OP HYMENOPTERA. 



First recurrent nervurc received by the second submarginal cell near its 

 middle, or between the middle and apex; clypeus^ prominent and 

 prolonged ; fifth abdominal segment 9 with a median longitudinal 

 furrow or rima; generally only the head and thorax metallic col- 

 ored Agaposteinon Smith. 



Body without metallic colors. 

 Abdomen smooth, shining, naked, generally red, or red and black, rarely 

 entirely black. 

 Fifth abdominal segment 9 without a median longitudinal furrow or 

 rima; face short and broad, subrugose; ocelli not unusually large. 



SpheeodeM Latr. 



Fifth abdominal segment 9 with a median longitudinal furrow or 



rima; face elongate, narrow, shining; ocelli unusually large and 



prominent Parasphec^odes Smith. 



AMoraen generally opaque, segments 1-4 or 5 almost always fringed at 

 apex with pale pubescence; fifth abdominal segment 9 with a me- 

 dian longitudinal furrow or rima; clypeus ^prominent, often pro- 

 longed; face without long pubescence Halivtiis Latr. 



1:}. — Second submarginal cell much narrowed towards the marginal ; body blue- 

 green, of small size ; legs and antennie simple in both sexes. 



€eratina Latr. 

 Second submarginal cell quadrate or nearly so, not narrowed towards the 

 margiual ; body large ; posterior legs % more or less deformed. 

 Apical joint of % antennre elongate, not dilated ; apical margin of the 



abdominal segments sometimes green Nomia Latr. 



Apical joint of % antennae short, dilated, excavated, spoon shaped. 



Euiioniia Cress. 

 14. — Third submarginal cell almost as long as the first and second combined, the 

 second elongate, cuneiform, narrowed and pointed at base, the first 

 recurrent nervure uniting with the second transvei-se cubital ner- 

 vure ; third submarginal cell scarcely narrowed towards the mar- 

 ginal, which is long and narrow Xylocopa Latr. 



Second submarginal cell rather longer than either the first or third. 



Marginal ceil rather short, obtuse at tip, not extending more than its 

 width beyond the apex of the third submarginal cell, which is very 

 much narrowed towards the marginal ; second submarginal cell 

 quadrate, not narrowed above; posterior legs 9 with long, dense 



pubescence Centris Fabr. 



Marginal cell long, pointed at tip, extending far beyond the apex of the 



third submarginal cell ; second submarginal cell strongly produced 



at base beneath ; maxillary palpi 2-jointed. 



Posterior tibife 9 flattened, dilated and more or less concave, polished 



and fringed with long hair (this arrangement is called the "cor- 



bicula"); sexes three, 'S 9 ? Bombus Latr. 



Posterior tibiae % 9 outwardly convex, dull and covered with short, 



dense pubescence ; sexes two, % 9 Apatlius Newm. 



Second submarginal cell smaller than either the first or third. 15. 



15. — Antennae %, conspicuously longer than in 9; clypeus % more or less yel- 

 lowish 16. 



Antennae % only slightly, or not at all, longer than in 9; clypeus not pale 

 colored 17. 



