A Monograph of Egyptian Diptera. . 61 



''blackish-brown with just the base and the tip of the femora and 

 "the basal third of the tibiae reddish-orange. Pubescence behind 

 "the femora not scarce, black on the anterior femora but pale 

 "near the base in pale specimens, on the hind femora pale yellow 

 "beneath and in front; the tiny bristles on the hind legs are all 

 "black about the tip of the femora and on all the tibiae except the 

 "usual yellow patch inside the hind pair about the tip." 



"Wings pellucid, subcostal cell and stigma distinctly brown- 

 "ish. Squamae dull yellow, with brownish orange margins. Halteres 

 "brownish yellow." 



Fran ilc: — "Similar; frons glittering blue-black at the vertex, 

 "then all covered* with yellow dust but sometimes with an in- 

 distinct middle black line connecting the vertex with a large shin- 

 "ing space above the antennae which space ranges from shestnut 

 "to black; the pubescence of the frons is all black, but on the tact' 

 "it is all pale, and there is scarcely any dark middle line, while it 

 "is all orange right away to the jowls; the hairs on the hack of 

 "the head are dense and conspicuously white, but yellow on the 

 "upper part ; the pubescence on the thorax is short, but on the 

 "scutellum short on the disc only, the hairs round the margin being 

 "fairly long. Legs very variable as in the male, from a normal 

 "form which would have them all dull orange except for a black 

 "ring about the middle of the hind femora, to specimens in which 

 "this ring is considerably extended and the hind tibiae and tarsi 

 I ome almost all blackish, and even until the front femora be- 

 "comc extensively darkened." 



"Length about 10 mm." 



"Mr. G.C. Bignell bred it from larva' which fed on Aphis 

 "pru/ii, and S. auricollis seems to he the main species to bo stored 

 "up by Crabro varus to provide food for its larvae, as in its bur- 

 "rows there occur masses of S. auricollis (4 males, 3 females) with 

 "their heads all pointing in one direction, while a pair of ,S'. 

 "balteatus occurred in company." 



Here again I only posses a single specimen of this interesting 

 species and therefore I can do nothing better than give Verrall's 

 description of it above in detail. This individual, a female, was 

 caught in my garden at Shoubra on December 20th, 1921, where 

 it was resting on a rose shrub. My specimen reems to agree with 

 the darkest forms of this extremely variable species, mentioned 

 by Verrall and its dark central knob, blackish antennae and arista, 

 very dark abdomen with its very obscurely luteous spots (Plate I 

 fig. 4), and its remarkably blackish legs makes it almost identical 

 with Rondani's S. nigritibius. 



