Volucella. 403 



rest the female shows the same two varieties as in the male; in the 

 female of plumafa the thoracai disc is generally still more yellow- 

 haired than in the male, the hairs on the middle being brown, or 

 thorax quite yellow-haired. Abdomen with no reddish spots on third 

 segment, 



Length 11 — 14 mm. 



As seen this species falls into two distinct varieties, so distinct 

 that they might without hesitation be taken for distinct species, but 

 they are now well known to be only varieties, and the two forms 

 have often been taken together in copula. The species is very Bomhus- 

 like, and the var. homhylans is like B. lapidarius, the var. plumata like 

 B. terrestris, but as said above it is rather doubtful whether this has 

 anything to do with mimicry. Verrall states (but he says expressly 

 that he estimates without accurate observation) that in England the 

 species for about sixty per cent. is like B. terrestris (and its allies) 

 and for about thirty eight per cent. like B. lapidarius, while two per 

 cent. may be of almost any Bombus colouring. I think it is about the 

 same in Denmark, at all events the var. plumata seems to be more 

 common than bombylans. Naturally the first author, Linné, described 

 the two varieties as distinct species {bomhylans and mt/stacea), and 

 the various varieties have given rise to the description of many species. 



V. bombylans is common in Denmark; at Copenhagen, Ordrup 

 Mose, Fure Sø, Geel Skov, Frerslev Hegn, Tisvilde, Nordskoven at 

 Jægerspris and at Sorø ; on Falster and on Lolland at Maribo, Bremers- 

 vold and in Kældskov; on Funen at Odense and Veflinge, and on 

 Fænø ; in Jutland in Nørholm Skov at Varde, at Horsens, Frijsenborg, 

 Rye near Silkeborg, Rebbild near Skørping .and Jerup near Frederiks- 

 havn, and on Bornholm. My dates are ^/e — ^^/t. It occurs in woods 

 and on meadows near woods and is here generally seen on various 

 flowers, especially on Umbelliferæ and Gompositæ, thuso ften on Garduus. 

 The larva was found at Tisvilde in the nest of B. siibterraneus or an 

 allied species in September (Weis) and in Dyrehaven in the nest of 

 an undetermined Bombus on ^^/s (Schlick). 



Geographical distribution: — Europe and in Asia Minor; towards 

 the north to northern Sweden, and in Finland andSiberia; it occurs, 

 as it seems, also in North America {facialis Willist. and evecta 

 Walk.). 



2. V. pellucens L. 



1758. Linn. Syst. Nat. X, 595 et 1767. XII, 2, 989, 62 et 1761. Fn. 

 Suec. 1826 {Musca). — 1775. Fabr. Syst. Entom. 773, 2 {Mmca) et 1805. 

 Syst. Antl. 224, 3 (Syrphus). - 1816. Fall. Dipt. Suec. Syrph. 19, 5 (Syrphus). 



26* 



