i^oKTH Amkkican 1)ii*ti;i{X. 2V) 



47. Face without gibbosity. 48 



Face witli gibbosity'; if restricted to the lower part, apd hence 



not conspiciioiis, face neitlier carinate nor unusually nar- 

 rowcfl. 52 



48. Face narrow throughout, not at ail carinate, the mysta.x com- 



posed of few long hairs ° Stenoprosopis 



Face of unusual width, obtusely carinate ; niyatax composed of 



numerous hairs and bristles 49 



41). The closed fourth posterior cell much widened at the expense of 



the discal cell which is narrowed in its middle. ** Synoixus 

 Fourth posterior cell not unusually broader towards. its base. 50 



-V). Mystax moderately thick, bristly, not wall-like. ® Dysclytus 

 Mystax fine-haired, long and thick, wall-like. ... 51 



•51. Second posterior cell widened near the base in front at the ex- 

 pense of the first posterior cell. ** Lophonotus 

 Second posterior cell not widened in front at the base. 



° TRICHOJfOTU.« 



52. Dorsum of thorax with bristles reaching to the front part, or at 

 least thickly hairy along the middle. .... 53 

 ■ Vestiture of the front half of the thorax short. . . 55 



5;^. Facial gibbosity slight, reaching nearly to the antennie. 



"DaSOI'HKYS 



Facial gibbosity very distinctly prominent, reaching much less 

 high. ....... ... 54 



54. Third joint of the antennae slender, linear. ° Pkotophanes 

 Third joint of the usual elongate elliptical shape. ° Dysmachus 



55. End lamellis of the oviduct ( 9 ) egg-shaped and wedged in. 



EOTOI.MUS 



End lamella; wholly free, nearly style-like. ... 56 

 5fi. Posterior border of the last ventral segment in the male more or 



less widened. . Maciiimcs 



Posterior border not widened ( S )■ • .57 



57. Legs prevailing shining yellow. NKOMO(mTHKRii8 

 Legs prevailing black, or light and opaque colored. 58 



58. Abdomen shining black above and below. . Stii.pnooa.ster 

 Abdomen not shining on both sides 59 



59. General color yellowish-gray or ash-gray, the legs with reddish 



yellow stripes or bands ; opaque. •* Epitrii-tus 



