56 Orthonhapha brachycera. 



Female. Frons broad, grey. Abdomen somewhat shorter haired 

 than in the male; front femora with somewhat scaly hairs towards 

 the apex, hhid femora with a row of scaly hairs on the ventral side 

 and a row of fine, bristly hairs on the postero-ventral side; hind 

 tibiæ with longish hairs and some bristles on the dorsal side, 



Lenglh 3 mm. 



This species may, I think, be best recognised from the curious loop 

 at the base of the penis, and in the female by the way in which the 

 legs are feathered. I have examined Zetterstedt's type-specimens, so 

 that my Identification is certain. 



Bh. ohscura is rare in Denmark, only one specimen, a male has 

 been taken in Lyngby Mose ^Vo 1909 (the author). 



Geographical distribution : — Northern Europe up to the northern- 

 most Scandinavia; it is not known south of Denmark. 



11. Rh. simplex Zett. 



1849. Zett. Dipt. Scand. VIII, 3035, 10-11 et 1855, XII, 4613, 10-11. 

 — 1903. Kat. palaarkt. Dipt. II, 229. 



Male. Eyes contiguous, the small frontal triangle grey; epistoma 

 grey. Occiput grey, with black hairs. Labrum a little longer than 

 the head is high; palpi black, with black hairs. Antennæ as long as 

 the head, black, the two basal joints slightly greyish, with short, 

 black hairs, the third joint somewhat elongated and attenuated to- 

 wards the apex. Thorax grey, dull, whithout stripes, only the hairs 

 giving the impression of the presence of three faint stripes. Dorso- 

 central and acrostichal bristles of moderate length, black, biserial, the 

 dorsocentral bristles longer and uniserial behind, quite in front they 

 are pluriserial and somewhat fusing with the hairs at the sides 

 of the disc. Further a humeral bristle, some posthumeral, three 

 or four notopleural, a pair of supraalar and a postalar bristle, 

 all black, but they are not much pronounced between the other, 

 somewhat strong hairs on the [sides of thorax. Scutellum has six 

 black marginal bristles. Pleura grey, metapleura with black hairs. 

 Abdomen somewhat robust, grey, dull; it is densely clothed with 

 somewhat strong, black hairs which are short above, longer at the 

 sides. Venter grey, more sparingly clothed with somewhat short hairs. 

 Exterior genitalia small, somewhat knob-like, blackish grey, slightly 

 pruinose; the lower lamellæ short, broad, directed somewhat upwards, 

 with black hairs at the margin; the upper lamellæ almost quite 

 hidden; the eighth "ventral segment forming a somewhat large, arched 

 plate below. Penis only sometimes seen above, between the lamellæ, 



