Criorrhina. 497 



apex, including all the tifth and fourth segments and the niiddle of 

 the hind margin of the third segment; it is all reddish-haired except 

 on the bluish side parts of second and third segments; on the apieal 

 part it is generally paler-haired and the hairs are longer and much 

 denser than in the male. 



Length 12 to nearly 15 mm. 



C. floccosa is, I think, a little more rare in Denmark than the two 

 preceding species, and it has hitherto only been taken on Sealand ; 

 Ordrup Mose, Ermelund, Dyrehaven and Tyvekrog. My dates are 

 25/5 — ^^/e. It oceurs in woods and thickets, I have taken my speci- 

 mens on flowers of Grataegus oxyacantha. 



Geographical distribution : — Europe down into Italy ; towards the 

 north to southern Svveden, but rare. 



4. C. asilica Fall. 



1816. Fall. Dipt. Suec. Syrph. 22, 10 (Syrphus). — 1822. Meig. Syst. 

 Beschr. III, 238, 14 (Milesia). — 1843. Zett. Dipt. Scand. II, 672, 2 et 

 1855. XII, 4653, 2 et 1859. XIII, 5083, 2. — 1862. Schin. F. A. I, 351. -^ 

 1901. Verr. Brit. Fl. VIII, 585,5, fig. 404. — 1907. Kat. palåarkt. Dipt. III, 

 123. — Xylota rufipila Meig. 1822. 1. c. III, 215, 4. 



Male. Vertex black, not pruinose, frons black, shining, with a 

 longitudinal furroM^, it is whitish pruinose at the sides; epistoma 

 w^hitish or yellowish white pruinose, the lower side parts black; vertex 



Fig. 170. Antenna of C. asilica c?, from the inside. X 40. 



w^ith long, yellow hairs, darker anteriorly, frons quite bare; epistoma 

 with only a few white hairs at the sides and on the eye-margins; the 

 epistoma shaped as in floccosa, but, however, less descending. Occiput 

 greyish yellow pruinose, the hairs yellow, or paler beneath and here 



3^2 



