Dolichopodidae. 289 



only dark in fasciatum; it is also here formed of coalesced bristles; 

 the front coxæ have generally some bristles or bristly hairs at the 

 apex; tlie middle coxæ have one or two bristles anteriorly at the 

 outer margin, the hind coxæ one on the outer side ; hind femora with 

 or without preapical bristle. Tibiæ with rather few bristles. The 

 males may have the front metatarsus a little thickened at the end 

 below; hind metatarsus more or less shorter than the second joint, 

 without bristles. Wings not broad, the mediastinal vein terminating 

 in the subcostal vein, the discai vein slightly curved ; the posterior 

 cross-vein about in the middle. The discai vein with a convexity on 

 the curve. Squamulæ with a distinct angulary lobe, bearing a long 

 fringe; the inner part of squamulæ with somewhat short hairs. 



The genus is distinguished from Porpht^rops by the more slender 

 shape and the less hairy and less bristly legs, by the much longer 

 antennæ in the male, with a very short arista, the distinct pubescence 

 of the third antennal joint and the arista, and by the bristle on the 

 hind coxæ; the wings are also less broad, and the curve of the discai 

 vein slight. It is distinguished from Syntormon especially by the 

 simple second antennal joint, further by the longer antennæ in the 

 male, the more haired occiput, and the exposed hypopygium. 



The developmental stages are not known. 



The species of Xiphnndrium occur on bushes, in low herbage 

 and grass in fens and on humid meadows, especially at the horders 

 of ponds and streamlets; they are generally not common, but per- 

 haps somewhat overlooked on account of their small size. I have 

 several times seen specimens of X monotrichum and caliginosum sucking 

 on spots of dew on the leaves, they stood then in a position with 

 the head quite down towards the leaf and the long antennæ lying on it. 



Of the genus 19 species are known from the palæarctic region; 

 5 have hitherto been found in Denmark. 



Tahle of Species. 

 Males. 



1. Coxæ yellow, apical spine on middle coxæ dark; ab- 

 domeii with yellow colouration; black coxal bristles 



about 3:2:1 1. fasciatum. 



— Posterior coxæ more or less grey; apical spine on 

 middle coxæ pale; abdomen without yellow colouration. . 2. 



2. Hind femora with a preapical bristle 3. 



— Hind femora without a preapical bristle ; black coxal 

 bristles 2—3 : 1— 2 : 1 4. 



3. Outer lamellæ ending with a single, long hair; coxal 



bristles 2 — 3:1—2:1, those on front coxæ white. . '^.monotrichum. 



19 



