Empididae. 53 



This species is especially distinguished by the nearly bare hind 

 femora, and the uniserial acrostichal bristles are also characteristic. 

 — Kowarz says: „Hintertarsen mehr als doppelt so lang, als die 

 Schiene", this must be a lapsus, and he also continues: „Metatarsus 

 von halber Schinenlånge." 



Rh. confonnis is very rare in Denmark, only one specimen, a 

 male has been taken at Silkeborg on 2^/5 1906 (A. Petersen). The 

 species is evidently a spring species, Kowarz took it in April; the 

 specimens were taken on a meadow, where they swarmed in the air 

 with the legs pendulous, and sat on bushes. 



Geographical distribution : — The species is hitherto only known 

 from Hungary, Britain and Denmark, the northern limit thus seems 

 to lie in our country. 



9. Rh. tarsata Meig. 



1822. Meig. Syst. Beschr. III, 45, 6. — 1842. Zett. Dipt. Scand. I, 

 430, 51, et 1849. VIII, 3034, 51. - 1862. Schin. F. A. I, 101. - 1903. 

 Kat. palåarkt. Dipt. II, 230. 



Male. Eyes contiguous, frontal triangle greyish black; epistoma 

 black. Occiput likewise black, slightly dusted, with black hairs. 

 Labrum scarcely as long as the head is high; palpi brownish wdth 

 brown hairs. Antennæ shorter than the head, black, the two basal 

 joints short-haired, the third not much elongated, somewhat attenuated 

 towards the apex. Thorax black, shining, without any design. Dorso- 

 central and acrostichal bristles somewhat long, black, biserial; the 

 hinder dorsocentral bristles long; there are some hairs at the sides, 

 but the dorsocentral bristles are distinct from them. Further a humeral 

 bristle, a weak posthumeral, about three notopleural, weak supraalar 

 and a postalar bristle, all black. Scutelium slightly 

 greyish dusted, with four black marginal bristles. 

 Pleura slightly dark greyish dusted, metapleura 

 with black hairs. Abdomen black, shining, with 

 short, black hairs, only slightly longer at the sides 

 m front ; venter black or blackish, sparingly haired. 

 Exterior genitalia black, the lamellæ directed up- 

 wards and the eigth ventral segment arched some- 

 what downwards (anus hians); the lower lamellæ ^j^ ^^ Rh^tarsata 

 with long, black hairs at the lower (posteriorly j^ale genitalia. 



pointing) margin ; the upper lamellæ somewhat 

 styliform and somewhat curved, lying above (in front of) the lower; 

 the eighth ventral segment with long, black hairs on the margin. 

 Penis a very thin, towards the apex exceedingly thin, simply curved 



