Therevidae. 139 



2. Silvery haired species; female without frontal callus . 7. annulata. 



— Not silvery haired species ; female with a frontal callus 3. 



3. Abdomen in both sexes quite yellowish; seventh seg- 

 ment in the female of the same colour 1 . subfasciata. 



— Abdomen with black markings or nearly quite black ; 



seventh segment in the female shining black 4. 



4. Wings without any blackish blotch 5. 



— Wings with a blackisk blotch running from the medial 

 cross-vein in a curve above the discai cell and down 



over the cross-vein closing this apically 3. arcuata. 



5. Abdominal segments more or less yellow with black 

 triangles or more semicircular spots ; the hind mar- 

 gins yellow; body more or less yellow haired above; 

 frontal callus in the female not reaching the ocellar 



tubercle 2. nohilitata. 



— Abdominal segments in the male withouth triangular 

 or semicircular spots; frontal callus in the female 

 either reaching the ocellar tubercle or very short or 



divided into two tubercles 6. 



6. Abdominal segments in the male nearly quite black, 

 only slightly brownish towards the hind margin; the 

 hind margins yellow; body chiefly black haired above; 



frontal callus in the female very short, transverse ... 5. circumscripta. 



— Abdominal segments in the male with smaller or larger 

 greyish or greyish yellow markings; frontal callus in 



the female not short and transverse ■....?. 



7. Abdominal segments in the male with greyish tri- 

 angular spots at the hind corners, the spots more or 

 less connected in the middle; hind margins yellowish 

 white or whitish; body chiefly black haired above; 

 frontal callus in the female large, reaching the ocellar 



tubercle 4. piebeja. 



— Abdominal segments in the male with a greyish or 

 greyish yellow, indefinitely bounded transverse band 

 on the apical half, more or less triangularly incised 

 in the middle; hind margins yellow to whitish yellow; 

 body more or less yellow haired above; frontal callus 



in the female divided into two tubercles 6. bipunctata. 



8. Female with a frontal callus (only the female known) 8. microcephala. 



— Female without frontal callus 9, 



9. Antennæ with the first joint thickened, longer than 



the second and third together 9. anilis. 



— Antennæ with the first joint not thickened, shorter 



than the second and third together 10, fnscipetmis. 



1. T. subfasciata Schum. 



1838. Schum. Arb. schles. Ges. vaterl. Kult. 1838, 58. — 1847. Loew, 

 Dipt. Beitr. II, 4, 2. - 1849. Zett. Dipt. Scand. VIII, 2982, 1-2. - 1862. 

 Schin. F. A. I, 165. — 1903. Kat. palaarkt. Dipt. II, 211. 



