Exorista. 307 



Female. Similar; frons a little broader, as broad as the eye. 



Lengtli 5 — 5,5 mm. 



E. auriilenta is rare in Denmark, I know only three specimens 

 from Tisvilde, bred from Hyponomeuta euonymella (I. G. Nielsen), 

 one from Maribo, bred from an undetermined lepidopterous larva 

 (Sønderup), and one specimen without locality. It is otherwise 

 known from Drepana jalcataria and cultraria, Mamestra pisi, Ahraxas 

 silvata^ Hylophila prasinana, Collix sparsata, Tephroclystia actaeata 

 and especially from Hyponomeuta cognatella and padella, further 

 from the non Danish Pygaera anachoreta, and fmally also from Lo- 

 phynis-cocoons. Nielsen has (Entom. Medd. 2, IV, 1909, 46) treated 

 its biology; he bred it from H. euonymella; the larva bores out of 

 the host larva, which at that time is reduced to an empty skin, and 

 it pupates in the cocoon; only one parasite developed in each host. 

 Nielsen found host larvæ in which, besides the larva of the present 

 species also one or two larvæ of Ptychomyia selecta were present. 

 The species has more than one generation in the year. 



Geographical distribution: — Europe down into France; towards 

 the north to southern Sweden. 



64. E^xOPista Meig. 



Species of medium or sometimes larger size, colour blackish 



with greyish pruinosity and often slightly reddish translucent at the 



sides of abdomen, but generally only in male. Head as broad as 



thorax, slightly convex or nearly flat behind and a little puffed out 



below, much higher than long. Frons in male narrow or broader, 



but always broader in female than in male, more or less protruding. 



1 Jowls not broad, at most about one fourth of the height of the eye. 



In both sexes ocellar (except lota) and inner vertical bristles, in 



female also outer vertical and two orbital bristles; sometimes weaker 



■ outer vertical bristles present in male. Behind postocular bristles black 



' hairs in one row or more, except in ajfinis. Frontal bristles descending 



to end of second antennal joint, or longer down to middle of cheeks, 



\ one to three uppermost reclinate in both sexes. Cheeks bare. Vibrissæ 



i only slightly ascending, at most to about one third of the height. 



I Eyes hairy. Epistoma somewhat retreating, a little reflected below. 



Antennæ inserted above middle of the eye, third joint from about 



i two to six times as long as second; arista with second joint short to 



! somewhat elongated. Thorax a little rectangular; three or four post- 



20* 



