318 ERNEST A. BACK. 



HETEROPOGON. 



Heteropogon Loew, Linnjea Ent., II, 488, 1847. 



Heteropogon Schiner, Fauna Austr., I, 132, 1862 



Anisopogon Loew, Berl. Ent. Zeit., XVIII, 377, 1874: changes 

 name to Anisopogon on account of prior use of Heteropo- 

 gon in Botany. 



Anisopogon Coquillett, Can. Ent., XXV, 20, 1893 (synopsis of 

 species) . 



Slightly to quite hairy species of medium size; thorax short, 

 much arched; head set very low in comparison with the 

 height of the thoracic dorsum, much broader than high; face 

 moderately broad, of equal width, hardly convex, without 

 protuberance; mystax dense and, on the oral margin, com- 

 posed of longer, denser, stouter hair, above with finer, more 

 sparse, pile, extending to base of antennae. Antennae short, 

 nearly approximate; the first two segments short, subequal, 

 more or less cylindrical; the third segment longer than the 

 basal segments taken together, very slender, tapering from 

 base toward tip; style very slender, bristle-like, shorter or 

 longer than the third segment. Front but little broader above, 

 on the vertex distinctly depressed, ocellar tubercle large and 

 very prominent. Abdomen above very bare; on the sides 

 and venter usually with longer pile; male genitalia very small, 

 downward directed. Legs slender, rather bristly, the front 

 tibiae without a terminal claw-like spur; the hind tibiae toward 

 the tip somewhat stouter; the hind tarsi a trifle shorter than 

 the anterior pairs, and of all, the metatarsi are markedly 

 elongate; in many species the front tarsi and middle tibiae of 

 the male bear characteristic hair markings which are wanting 

 in the female; pulvilli normal. All the submarginal and pos- 

 terior cells wide open; the anal cell closed or slightly open. 



Type. — Dasypogon manicatus Meigen. 



SYNOPSIS OF SPECIES. 



1. Scutellum (except sometimes the extreme base) black or black- 



ish 2. 



Scutellum and face yellow, abdomen yellow, marked with five 

 black fasciae, wings pale yellow vespoides. 



2. Abdominal segments 1-4 wholly black 3. 



Abdominal segments 3-6 (except sometimes their lateral margins) 



reddish 6 . 



