Plagia. 479 



a pair of erect diverging præapical bristles near the margin. Three 

 sternopleiiral bristles. Pteropleiiral bristle represented by some long 

 hairs. Abdomen elongated conical, atteniiated behind, fifth segment 

 conical in shape; excavation on second segment reaching hind mar- 

 gin; there are only marginal, or (in non Danish species) discai and 

 marginal bristles; on second segment none or a pair of weak marginal 

 bristles. Legs with anterodorgal bristleg on hind tibiæ imequal; claws 

 and pulvilli elongated in male; front tarsi in female simple. Wings 

 with first posterior cell narrowly open, ending long before apex of 

 wing; discai angle obtuse, with a fold as veinlet; posterior cross- vein 

 very oblique, issuing below medial cross- vein; bristles on cubital 

 vein stretching towards medial cross- vein; a very small or no costal 

 spine. 



The species are parasitic on Heterocera; they belong, so far known, 

 to Pantel's group 6, and they form a secondary breathing hole. 



Of the genus 4 European species are known, one occurring in 

 Denmark. 



1. P. ruricola Meig. 



1824. Meig. Syst. Beschr. IV, 299, 104 {Tachina) et 1838. VII, 201, 5. — 

 1844. Zett. Dipt. Scand. III, 1093, 90 {Tachina). — 1862. Schin. F. A. I, 437. 



— 1889. B. B. Denksclir. Akad. Wiss. Wien, LVI, 101, Tab. V, Fig. 81 et 1891. 

 LVIII, 354 {Cyrtofhlebia). — 1896. Pand. Rev. Entom. XV, 8, 8 {Exorista). 



— 1907. Kat. palåarkt. Dipt. III, 369. — 1921. Baer, Zeitschr. f. angew. Ent. 

 VII, 364. — 1924. Stein, Arch. f. Naturgesch. 90, 6, 121, 2. — Cyrtophlebia 

 nigripalpis Rond. 1859. Dipt. Ital. Prodr. III, 189, 2. — C. huccata B. B. 1894. 

 1. c. LXI, 618. — 1909. Villen. Wien. Ent. Zeitg. XXVIII, 333. 



Male. Frons above a little broader than the eye; cheeks narrowing 

 downwards. Orbits, cheeks and jowls whitish grey; frontal stripe 

 igrey or blackish grey, seen from in front whitish. Outwards to the 

 frontal bristles a row of bristles continuing down the cheeks to the 

 lower corner of the eye, two of them on the orbits specially strong. 

 Orbits and cheeks besides the bristles with some few hairs. Jowls besides 

 the oral bristles only with some hindmarginal bristles, for the rest bare. 

 Occiput grey, with whitish hairs. Eyes with short, pale hairs. Antennæ 

 black, basal joints grey; arista short, thickened to near apex. Palpi 

 blackish. Thorax black, greyish pruinose, with four equally distant 

 black stripes, the median abbreviated behind ; scutellum dark. Thorax 

 black-haired. Abdomen black, shining, third, fourth and basal part 

 of fifth segment bluish grey pruinose; abdomen black-haired, on 

 second segment a pair of weak marginal bristles, on third a pair 



