170 Syrphidae. 



is more parallel-sided, thorax less coarsely punctate and the hind 

 femora setulose beneath. — The species varies with regard to the 

 scutellar bristles; my material consists of one Danish male and three 

 females and farther of two males and two females from Verrall's 

 collection; two of the males (a Danish and an English) have fine, 

 long, black bristles, the third (an English) similar bristles but all yellow; 

 of the females one (Danish) has somewhat short, black bristles, another 

 (English) longer, black bristles, and three others (two Danish and an 

 English) similar but partly yellow bristles. 



C. Bergenstammi is rare in Denmark, I only possess four specimens, 

 a male and three females; two of the females arc taken in Højenbæk 

 Dal at Vejle on ^/s 1908 (the author) and one at AUerup in Vend- 

 syssel on 2/r. 1909 (Esben Petersen); the male is without particular 

 locality. 



Geographical distribution: — Northern and middle Europe down 

 into Austria; Becker records it from Scandinavia as he found a 

 specimen in Loew"s collection with Zetterstedt's handwritting; it is 

 otherwise not known from Scandinavia. 



21. C. gigantea Zett. 



1838. Zett. Ins. Lapp. 612. 7 et 1843. Dipt. Scand. II, 791, 16 et 1849. 

 VIII, 3168, 16 et 1859. XIII, 6015, 16 (Eristalis). — 1894. Beck. Nov. Aet. 

 Leop. Carol. Akad. LXII, 429, 78 et 507, Fig. 66—67. — 1907. Kat. palåarkt. 

 Dipt. III, 28. — Eristalis olivacea Zett. 1838. Ins. Lapp. 611,6 et 1843. 

 Dipt. Scand. II, 791, 15 et 1855. XII, 4664, 15 et 1859. XIII, 6015, 15. — 

 1894. Beck 1. c. LXII, 247. 



Male. Eyes with longish hairs, yellowish above, paler below. 

 Frons æneous black with a longitudinal groove; vertex and frons 

 black-haired. Epistoma pruinose below the antennæ, for the rest 

 shining; it is hollowed below the antennæ, the central knob somewhat 

 large and prominent, and between it and the upper mouth edge the 

 epistoma somewhat hollowed; it is only little prominent below and 

 slightly descending. Eye-margins of medium breadth, somewhat pruinose, 

 with longish, white hairs ; at the lower margin of the eye a brownish 

 spot. Occiput greyish pruinose, the hairs whitish below but almost 

 exclusively black above. Antennæ not large, third joint squarely 

 roundish; they are black or third joint blackish brown; arista some- 

 what long, very short pubescent or apparently bare. Thorax æneous 

 black, shining, finely punctate ; it is clothed with somewhat long, erect, 

 black or brownish black hairs, partly mixed with paler hairs; there 

 are notopleural, supraalar and postalar brislles, but not very con- 

 spicuous; scutellum with numerous, somewhat long but fine marginal 



