A Monograph of Egyptian Diplera. 53 



8. sykphus FABR, 



Fabr., Syst. Entom., 762. 172. (1775). 



SYNONYMY:— Scceva Fabr., Syst. Antl. 248.57. (1805). 



Psilogaster Lioy, Atti. Instit. Veneto, (3) IX. 753. 12. (Psylo- 

 gaster) (1863-64) nee Blanch., Hym., 1840. 



Epistrophe Walk., Ins. Sanders., III. I. 242. (1852). 



Species of moderate size, blackish or aeneous and clothed with 

 moderate pubescence; always with yellowish markings on the face, 

 scutellum and abdomen, but not on the pleurae, even though the 

 yellow colouring may be sometimes very faint on the face and 

 scutellum. Eyes always touching on the frons in the male, but well 

 separated in the female; they are usually bare and sometimes hairy. 

 Antennae moderate in length and in shape; it always bears near 

 the base of the oval third joint, a bare arista. 



Wings possess the most typical Syrphus venation, with Radius 

 4 + 5 almost straight; alula fairly well developed and when at rest 

 the wings lie parallel over each other on the abdomen. 



The metamorphoses of several species of Syrphus have been 

 studied and in the case of some species, have been known for a 

 long time. S. ribesii (a very common European species) was ob- 

 served by Linnaeus and Fabricius who both speak of the larva as 

 occuring "inter Aphides." Reaumur mentions the larva of S. bal- 

 teatus (?) among Aphids on Pr units and Ribes. Verrall states that 

 it is probable that De Geer's exhaustive describtion of the meta- 

 morphoses of his Musca vinastri referred to S. corolla'. Fallen also 

 found the larva of S. corolla' feeding on Aphids on Brassica 

 oleracea. Bouche has also described the larvae of S. ribesii and S. 

 I>id teat us. Schiner states that he found the pupa of S. nitidicollis 

 in April under a stone in a humid meadow and that it meta- 

 morphosed after a short interval. Lundbeck says that according 

 to Brauer, Weyenberg mentioned the developmental stages of S. 

 balteatus and corolla?. Verrall says that S. balteatus and auricollis 

 have been bred from larvae found feeding on Aphis pruni. Martelli 

 mentions the larvae of S. ribesii, bifasciatus, balteatus and auri- 

 collis as feeding on Aphis brassicce. Lundbeck has also found 



