314 Syrphidae. 



says that eight specimens labelled luniger were probably Catahomha 

 selenitica, but this is not correct, these eight specimens are just my 

 arcuatus; VerraU's expression shows how much the species is similar 

 to a Catabomba, but he has failed to observe the bare eyes. On 

 pag. 338 — 34 Verrall speaks of four specimens from North America i 

 Bigot's collection, labelled lapponicus, which he considers as a bare- 

 eyed Catadomba, and which he thinks may perhaps be the true European 

 S. lapponicus; after the above it would be my arcuatus, but as shown 

 below, it is probable that neither lapponicus nor arcuatus occur in 

 North America. Osburn (Journ. New York Ent. Soc. XVIII, 1910, 53) 

 records S. arcuatus, under which he includes both arcuatus and lap- 

 ponicus, but according to his figure of the broad frons in the male 

 and the dipped cubital vein it cannot be my arcuatus nor lapponicus. 

 At the same place the author describes a new species. S. perplexus, 

 likewise with a broad frons, but with an almost straight cubital vein : 

 the colour of the frons of the female shows that the species cannot 

 be my arcuatus. Our two species thus do not seem to occur in 

 America, and the species from Bigot's collection mentioned by Verrall 

 is probably one of Osburn's species. Osburn says that in both his 

 species some males have an area of enlarged eye-facets, others not; 

 among his specimens of arcuatus there were only few males with the 

 area and none from Europe, in perpdexus most males had the area. 

 I do not think this possible; the character of a distinctly marked area 

 of large facets is according to my experiences not variable in the same 

 species ; supposed that the author has separated his specimens correctly 

 I should be inclined to think that the different condition might be due 

 to exsiccation, which sometimes may cause an area of larger facets 

 less easy to observe. 



21. S. bifasciatus Fabr. 



1794. Fabr. Ent. Syst. IV, 305. 101 et 1805. Syst. Antl. 248. 2 

 {Scaeva). — 1822. Meig. Syst. Beschr. III, 309, 52. — 1843. Zett. Dipt. 

 Scand. IL 713. 15 et 1855. XII, 4656, 15 {Scaeva). — 1862. Schin. F. A. I. 

 309. — 1901. Verr. Brit. Fl. VIII, 387, 21, figs. 299—301. — 1907. Kat. 

 palåarkt. Dipt. III, 61. 



Male. Vertex elongate, black: frons yellow, with a large, black 

 lunule above the antennæ, and behind a little dark pruinose. Epistoma 

 yellow, the mouth edge and lower lateral parts darkened to black. 

 Jowls black or greyish, more or less yellow behind. Vertex yellow- 

 haired behind, black-haired in front, frons black-haired; epistoma 

 yellow-haired, above at the sides with some black hairs. Occiput 

 greyish yellow pruinose, the hairs yellow, upwards dark yellow: no 



