Asilidae. 81 



with the coxæ greyish pruinose witli long, whitish hairs; feraora black, 

 tibiæ yellowish ferrugineous with black tips, tarsi black, only the 

 extreme base of the metatarsi, and sometimes of some of the following 

 joints, reddish. The hairs on the femora yellowish, only black above 

 just at the apex, on the tibiæ chiefly black, but intermingled with 

 yellow, especially on the anterior tibiæ; long, thin hairs are found 

 on the ventral side of the femora, on the hind femora also on the 

 posterior side, on the ventral side of the front tibiæ and a few on 

 the ventral side of the middle tibiæ; they are for the most part yellow, 

 but on the anterior femora there is a row of stronger, black ones, 

 and on the hind femora a similar row of yellow; spine-like bristles 

 are found on the ventral and anterior sides of the posterior femora, 

 on the dorsal and posterior sides of the front tibiæ and on the various 

 sides of the posterior tibiæ with exception of the posterior side of the 

 hind tibiæ, fmally as usual a few apically on the femora; they are 

 nearly all black, only generally yellow on the front side of the hind 

 femora. The spine-like bristles are relatively weak, not much stronger 

 than the strong hairs. The spine-like bristles on the tarsi are black. 

 Wings hyaline, slightly greyish at the apex but the border of the 

 greyish fumigation not sharp; veins brown. Halteres yellow. 



Female. Ovipositor shining black, the sixth and seventh segments 

 take part in ils formation; the lamellæ free; the ovipositor is clothed 

 with black hairs which are long, especially below. 



Length 12 — 17 mm. 



The pupa has a length of 15 mm.; the spines on the flrst abdo- 

 minal segment are not longer than those of the following segments, 

 and they are only slightly recurved at the apex. 



This species is easily known by its blue last abdominal segments 

 (see below about the nearly related N. socius). 



N. cyanurus is common in Denmark; Ermelund, Bøllemosen, 

 Frederiksdal, Geel Skov, Hillerød, Tyvekrogen, Grib Skov, Tisvilde, 

 Svenstrup between Roskilde and Ringsted; on Lolland at Maribo; on 

 Funen at Odense, Langensø and Veflinge; in Jutland in Greisdalen at 

 Vejle, at Horsens, Frijsenborg, Silkeborg, Støvring near Randers and 

 Frederikshavn; finally on Bornholm at Hasle. My dales are ^'Vn— '^'9, 

 It occurs in woods, often, but not exclusively, on dry localities and 

 often in rathei- great numbers; it is generally seen sitting on the stems. 

 A larva was found in Bøllemosen in a mole-cast on -^/t;, it pupated 

 "/(i and developed on ^'-/t; , other larvæ were found in Geel Skov in 

 the earth on ^'•'/4, they pupated ^/ri and developed ^'5. Pupæ have 

 been found in Bøllemosen in mole-casts on "'/g, they developed on ^*'t;, 

 and in Geel Skov in the earth on ^/s developing on ^','5. — I once 



Diplera Danica. II. (^ 



