ASILIDJE. 55 



9. Anterior intercalary vein continuous or nearly so with the fourth vein, 

 the last section of the latter oblique, closing or much narrowing the 

 broad first posterior cell. . . . MICROSTYLUM Macquart. 

 Last section of the fourth vein continuous with the preceding section, 

 the first posterior cell not closed or narrowed (Central and South 

 America) ARCHILESTRIS (Schiner) Loew. 



10. Abdomen cylindrical, not narrow at the tip, elongate ; near the proxi- 



mal margin of the second and third segments with a white-pollinose, 



emarginate cross-band ; wings dark. V. . DIZONIAS Loew. 



Abdomen less elongate, with five or six white-pollinose (interrupted or 



entire) cross-bands. . . ." . . . 11 



11. Scutellum with bristles; veins at the outer ends of the discal and 



fourth posterior cells parallel. . ORTHONECROMYIA Williston. 



Scutellum without bristles; veins at the outer ends of the discal and 



fourth posterior cells not parallel 12 



12. First posterior cell open, scarcely narrowed; face broad. 



LAPHYSTIA Loew. 

 First posterior cell closed or much narrowed. . TRICLIS Schiner. 



13. Antennae elongate, composed of five joints ; nearly bare species. 14 

 Antennae less elongate or short, composed of three joints with or with- 

 out a short or slender style. ....... 15 



14. First and second joints of the antennae of nearly equal length, the third 



elongate, the fourth short, fifth elongate and densely pubescent ; 

 third and fourth not lobed at tip. . CERATURGUS Wiedemann. 

 First joint about three times the length of the second, third elongate, 

 the fourth and fifth of nearly equal length; third and fourth joints 

 at the tip with two lobes or processes, reaching to about the middle 

 of the following joint. . " -. .', - . . MYELAPHUS Bigot. 



15. Style of antennae short, thick, obtuse, not easily distinguishable from 



the third joint, or if so forming apparent joints ; antennae more or 



less elongate. . 16 



Terminal style small, more slender than the joint, apparent; antennas 

 shorter. . ; ... . ... . . . . 18 



16 Nearly bare species; face flattened, bare, except below. Small or 

 rather small species, shining or metallic black, with narrow or cylin- 

 drical abdomen and large wings 17 



Thickly pilose species, the bristles few and hair-like ; antennae spring- 

 ing from a convexity, the facial profile thence receding to the facial 

 tubercle, which is situated upon the lower part of the face ; abdo- 

 men short; head narrow. . . . . DICOLONUS Loew. 



