81 



Genus S ARGUS, F. 



Sargus, Fabricius, Ent. Syst. Supp. pp. 549, 066 (1798) ; Brunetti, 

 Bee. Ind. Mus. i, p. 104 (1907). 



Genotype, Musca cupraria, L. ; by designation of Latreille 

 Consid. Gen. (1810). 



Head hemispherical, attached to thorax by a slender neck, as 

 wide as broadest part of thorax ; face slightly projecting, pu- 

 bescent ; ocelli placed well forward on vertex in a short isosceles 

 triangle, equidistant in some species ; eyes bare, separated in 

 d" by a narrow frons, wider apart in $ , upper facets in <$ 

 scarcely larger than lower ones. Antennae short, in profile placed 

 below middle of head ; first two joints bristly, short, subequal ; 

 3rd joint shortly conical or roughly rounded, with four annula- 

 tions ; arista subapical, long, bare, except at base. Thorax with 

 anterior part oblong, widened towards base of wings, posterior 

 part of dorsum rounded ; scutellum unarmed, usually concolorous 

 with the metallic-green dorsum and bearing the same short 

 pubescence. Abdomen much longer than thorax, with parallel 

 sides or broader posteriorly, brilliantly shining metallic, the 

 6 usually green or golden brassy, the 5 more often blue or 

 violet, moderately pubescent ; genitalia small. Legs simple, 

 rather long and thin; metatarsi long. Wings generally longer 

 than abdomen, over which' they fold when at rest; of the usual 

 Stratiomyid type ; costal vein nearly reaching wing-tip ; anterior 

 cross-vein connecting the praefurca (instead of the 3rd vein) with 

 the discal cell, thus creating the appearance of the 3rd vein being 

 twice forked ; 4th vein with three terminations, barely or not 

 reaching wing-margin ; posterior cross-vein distinct. Alar 

 squamae of moderate size, thoracic pair elongate, very prominent. 



Range. World-wide. 



Life-history. That of several European species is known, the 

 larvae living in garden-mould, cow-dung, and in the elm. 



Some attempt has been made to supplant the name Sargus on 

 the ground of its being preoccupied, but the name is too old to be 

 changed now. Verrall also disputes the validity of the alleged 

 preoccupation. 



Table of Species. 



1. Wings dark brown ; length 14-18 mm gemmifer, Walk. 



Wings yellowish 2. 



2, Legs all yellow metallinus, F. 



Hind tibias with broad blackish basal band mactans, Walk. 



52. Sargus gemmifer, Wall 



Sargus gemmifer, Walker, 



Sargus magnificus, Bigot, 



(1879); Brunetti, Rec. ] 



d 2 • Head with frons, though very narrow, parallel-sided fo 



Sargus gemmifer, Walker, List Dipt. Brit. Mus. iii, p. 516 (1849). 

 Sargus magnificus, Bigot, Ann. Soc. Ent. France, (5) ix, p. 222 

 (1879); Brunetti, Rec. Ind. Mus. i, p. 106 (1907). 



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