F. R. COLE 61 



Synopsis of Species 



1. Male orange to brownish yellow with dark brown spots on the al)dorainal 



spiracles. Female y)rown dispar Macquart 



Not colored thus 2 



2. Brown species averaging 7-9 mm. in length; the wings infuscated. 



incultus O. S. 

 Smaller species; wings usually hyaline 3 



3. Body shining blackish, with unusual!}' long, erect brownish pile on thorax. 



niger new species 

 Pile of body shorter; ground color of body usualh- brownish 4 



4. Abdomen mostly reddish above rufoabdominalis new species 



Abdomen mostly brown or blackish 5 



5. Humeri usually yellowish 6 



Humeri usually blackish 7 



6. Pleura brownish yellow; scutellum blackish brown. 



Small species, known only from Pacific Coast region . . aedon Townsend 

 Scutellum usually more or less yellow; the white posterior margins of ab- 

 dominal segments sharply defined costatus Loew 



7. Legs dull yellowish, the coxae black borealis new species 



Legs more or less blackish or brown 8 



8. Abdomen largely white above; venter white except a transver.se band on 



the last segment , albiventris Johnson 



Abdomen not marked in this manner 9 



9. Pile of body whitish 10 



Thorax with reclinate yellow i)ile; rims of squamae blackish. Rather small 

 species pallidipennis Loew 



10. Rims of squamae black, hind margins of first three abdominal segments 



narrowly white. Legs blackish melampus Loew 



Rims of squamae yellowisli. Pile of thorax quite long and erect. Very wide 

 white posterior margins on male abdominal segments. Legs marked with 

 yellow marginatus new species 



Ogcodes melampus 



Oncodes melampus Loew, Centuries, x, p. 23(i. 



"Black, humeri, margin of tegulae, all of legs and veins of wing concolorous, 

 abdominal segments with white jjostcrior borders, ventral segments white, 

 each with basal black band. Length, 2f lines. Wing, 2 ",',2 lines. 



"Black, pile whitish, not sublutescent. Humeri of like color with rest of 

 thorax. Abdomen with segments posteriorly white margined, border of first 

 segment narrowest, borders of second and third narrow and equal, that of the 

 following segments a little wider and less even; venter white, first segment black, 

 toward the sidc^s wider and suddenly dilated near the margin of the abdomen. 

 Legs all black. Halteres fuscous black, tegulae whitish, black margined. 

 Wings hyaline, pale ashj' tinge, veins all black, cf and $ ." 



Habitat. — California (H. Edwards). 



TRANS. AM. ENT. SOC, XLV. 



