ODYNERUS. 251 



„ , T . . 85. f proctus. 



b. Very large species. < ' 



86. I consors. 



6, 6. Species of medium or small size. 



7. Metathorax forming on each side a lateral angle. 



8. Superior angles of metathorax separated from post- 



scutel by a fissure or a notch. 

 Superior angles produced into erect spines ; scutel 

 yellow. 87. scutellaris. 



9, 9. Superior angles not spined. 



10. Lateral angles acute ; margin of 2d segment 

 reflexed; scutel black. 82. Hidalgi. 



10, 10. Lateral angles obsolete; margin of 2d segment 

 not reflexed ; scutel maculate. 

 11. Metathorax very sharp ; 1st segment broadly 

 margined with yellow. 100. titrjiis. 

 11, 11. Metathorax not sharp; 1st segment not mar- 

 gined in the middle. 88. Cordovx. 



8, 8. Superior angles of metathorax not produced. 



9. Scutel yellow or maculate ; clypeus J yellow; wings 

 ferruginous. 

 10. Second segment margined with yellow. 

 11. Smaller; more slender ; scutel yellow. 



98. spectabilis. 

 11, 11. Larger, less slender, scutel maculate. 



91. J apical is. 

 97. {formosus. 

 10, 10. Second segment mostly yellow. 



96. sulfureus. 



9, 9. Scutel black ; clypeus 9 rufous or black and yellow. 

 10. Ornaments of the body bright yellow. 

 11. Wings smoky. 92. arvensis. 



11,11. Wings smoky-ferrnginous. 94. annulatus, 

 10,10. Ornaments dull yellow; wings ferruginous; 

 body rather pubescent. 91. Alvaradi. 



7, 7. Posterior face of metathorax more or less orbicular, not 

 forming two lateral angles. 

 8. Superior edges of metathorax sharp, produced, separa- 

 ted from post-scutel by a distinct fissure or a notch. 

 9. Segments 1, 2 margined with luteous. 



101. Me gar a. 

 9,9. Segments 2, 5 margined with yellow or luteous. 

 10. Second segment without yellow maculse. 

 11. First segment only maculate on the sides. 



88. Cordova;. 

 11, 11. First segment margined with yellow. 

 12. Scutel maculate with yellow. 



13. Edges of the concavity of metathorax very 

 sharp. 100. turpis. 



