Exorista. 317 



yellow hairs and rows of black hairs behind postocular bristles. Eyes 

 pale-hairy. Antennæ black, third joint about thrice as long as second; 

 arista thickened in less than basal half, second joint distinct, not 

 ■elongated. Palpi yellow. Thorax bliiish black, somewhat shining, 

 grey or bluish grey pruinose, more grey at the sides, with four black 

 stripes, the median narrow, diverging and abbreviated behind, 

 the lateral broader, interrupted at the suture; scutellum with the 

 apical part reddish. Thorax black-haired; four postsutural dorso- 

 centrals. Scutellum with four marginal bristles on each side, the 

 apical Crossing. Tliree sternopleural bristles. Abdomen somewhat 

 elongated conical, black, somewhat shining, a little reddish trans- 

 lucent at the sides; third, fourth and fifth segment grey pruinose, 

 shifting with dark tessellations according to view; a middle stripe 

 and somewhat narrow hind margins to the segments black. Ab- 

 domen black-haired, with only marginal bristles, a pair on second, 

 four on third and a row on fourth segment; some of the hairs on the 

 disc may be more or less bristly developed. Legs black; hind tibiæ 

 with an anterodorsal row of unequal bristles with some longer bristles 

 in the upper half, the one about the middle strongest; claws and 

 pulvilli somewhat elongated. Wings a little tinged; veins brown; 

 first posterior cell ending a little before apex of wing; discai angle 

 obtuse and not sharp; apical cross-vein concave; posterior cross-vein 

 doubly curved. Squamulæ white. Halteres brownish. 



Female. Similar; frons as broad as the eye or fully; orbits fully 

 as broad as frontal stripe. 



Length. About 8 to 11 mm. 



E. glauca is common in Denmark; Dyrehaven, Rørvig and in 

 Jutland at Frijsenborg, Ry, Laven and Buderupholm; the dates 

 are in July and August. The species is parasitic on Dasychira pudi- 

 bunda, Parasemia plantaginis, Acronycta psi and tridens, Abraxas 

 grossulariata and on the Tenthredinid Abia sericea. 



Geographical distribution: — Europe; towards the north to 

 middle Sweden. 



Remarks : E. glauca belongs to a group of very nearly related 

 and difficult species; the above synonymy therefore must be taken 

 with precaution, as also the enumerated hosts. See Villeneuve, Wien. 

 Ent. Zeitg, XXXII, 1913, 121 under Parexorista clavellariae. — I have 

 examined Zetterstedt's types to T. stulta and Hke Stein I fmd it 

 identical with the present species. 



