f'HAKLES r. ALEXANDER ^6i) 



2G. Thoracic dorsum with three coiiiplcto cl;irl< brown stripes 27 



Thoracic dorsum without three dark brown stripes 28 



27. Wings broader, the tip not iufuscated; femora yellow tipped with 



brown. (Eastern United States) complexa Osten Sacken" 



Wings narrower, the tip narrowly infuscated; femora yellowish brown 

 at the tip and with a postmedial brown annulus. (Lesser An- 

 tilles; Guiana) annulata Williston" 



28. Thoraxlightyellow with adark narrow pleural stripe. (Central Amer- 



ica) pleuralis Alexander" 



Thorax without a pleural stripe 29 



29. Head and abdomen with metallic reflections; prothorax brownish; 



femora brownish black. (Cuba) chalybeiventris Loew" 



Head gray without metallic reflections; prothorax dull yellow; femora 

 yellow with the tips broadly brown. (I^olivia) 



jocosa Alexander" 



Genus ORIMARGA Osten Sackcn 

 18(59. Orimaryn O.^ten Sacken, Mon. Dipt. \. Am., iv. 120. 

 Orimarga punctipennis sp. n. 



Thorax and heatl bluish gray; legs very i)jile. alimisl whitish; wings 

 spotted with brown. 



Male. — Length, 7 mm. ; wing, 4.4 mm. 



Rostrum rather elongated, dark brown, the palpi brownish black. An- 

 tennae with the basal segments light brown, the flagellum broken. Head 

 with a uniform light gray bloom. 



Thoracic dorsum brown with a thick blue-gray bloom. Pleura yellow- 

 ish brown. Haltcres rather short, brown, more yellowish at the base. Logs 

 with the coxae and trochanters yellowish brown, the remainder very pale 

 whitish brown except the apical tarsal segments which arc brown. Wings 

 almost hyaline, the veins brown; dark brown dots as follows: the largest 

 at the tip of Sc, others at the base of Rx, tip of Ri, and on cross-vein r, 

 basal deflection of R^.^ and cross-vein r-m and faint marks on the basal 

 deflection of Cui and at the fork of Cui and Mi. Venation: see pi, IV, fig. 3. 



•Abdominal tergites dark brownish black, the stcrnites paler. 



IlabitaL—Burticii, February- 11, 1913, 

 Holotype, cf, Bartica, February 11, 1913. 



=' 1859, complexa Osten Sacken, Proc. Acad, Xat. Sci. Phila, 1859, 223. 

 (genoti-pe). 



" 1896, annulala Williston. Trans. Ent. Soc. Lond., 1896, 290, pi. x. 

 fig. 63. 



" 1913. pleuralis Alexander, Psyche, xx, 45, 46, 



" 1861. chalybeiventris Loew, Wien. Entomol. Monatschr., v, no. 2, 

 33, 34 (Rhamphidia). 



" 1913. incosa Alexander. Ent. \ew.s, xxiv. 440, 441. pi. 16. fig. 3. 



TRANS. AM. ENT. .SOC, XI-. (18) 



