Paragus. 5 1 



at the eye-margin an elongated, grey dust spot; it has yellow hairs 

 while the vertex is black-haired. Epistoma with a broad, black middle 

 stripe. 



Length 5,5 — 6,7 mm. 



This species varies considerably with regard to the colour on ab- 

 domen, but hitherto only the form described above has occurred in 

 Denmark. Otherwise it varies from the palest form with only base of 

 abdomen black (testaceiis), through forms as the described {hicolor) or 

 with the red middle part of abdomen smaller {arcuatus, tæniatus) or 

 only present on third segment {zonatus)^ further with only red spots 

 on second and third segments [^lacerus), to forms with only apex red 

 (ruficauda). In the darkest forms the scutellum may be unicolorous. 

 Also the hairiness of abdomen and its colour vary, sometimes forming 

 distinct pale or white fasciæ. Finally the size may vary, from small, 

 rather narrow to larger and broader specimens; the size is, however, 

 not so much varying in the few known Danish specimens. 



F. bicolor seems to be rare in Denmark, only six specimens are 

 known, two without particular locality (Schiødte) and four from Jerup 

 near Frederikshavn (Th. Mortensen), the latter taken on ^^/t. It occurs 

 on sunny and sandy piaces as sandy grass-fields, sitting on the grass. 



Geographical distribution:— Videly distributed species, occurring 

 over all Europe, towards the north to middle Sweden, and in Fin- 

 land; further in North-Africa, and also in North America. 



3. P. albifrons Fall. 



1817. Fall. Dipt. Suec. Syrph. 60, 6 (Pipiza). — 1822. Meig. Syst. 

 Beschr. III, 181,8. — 1843. Zett. Dipt. Scand. 11,851,4. — 1862. Schin. 

 F. A. I, 258. — 1900. Verr. Gat. europ. Syrph. 21. — 1907. Kat. palåarkt. 

 Dipt. III, 1. — Paragus ater Meig. 1822. Syst. Beschr. III, 182, 9. — 

 Syrphus thymasiri Fabr. 1781. Spec. Ins. II, 433, 60. 



This species is very like hicolor, but the abdomen is quite black; 

 the hairs on abdomen form rather obvious white or pale yellow 

 fasciæ on second, third and fourth segments. The hind margin of the 

 fourth ventral segment in the male is straight or almost so. Scutellum 

 has only the tip pale, and even this may be rather obscured. The hind 

 tibiæ have always a dark ring, and also the anterior tibiæ may be 

 obscured about the middle. The tendency of the eye-pubescence to 

 form bands is less obvious. The species is in general smaller than 

 bicolor. 



Length 4,8 — 6 mm. 



This species is, so far Danish specimens are concerned, at once 

 distinguished from hicolor by its black abdomen. Verrall has raised 



