attempted division of british insects. 393 



Natural Order. — Tachydromites. 



Larva and pupa unknown. Imago, with antennae five-jointed ; the 

 basal and second joints oblong, the third elongate and robust, 

 the fourth and fifth forming a seta, which is bent nearly at a right 

 angle with the third ; labium short, bilobed ; ocelli three ; wings 

 very large and wide, lying horizontally on the back ; body rather 

 pilose, short, stout, pointed. Inhabits woods, hedges, and um- 

 bellate flowers, preying on dipterous and minute hymenopterous 

 insects ; black, brown, or fulvous. Hemerodromia, Tachydromia, 

 Platypalpus, Drapetis. 



Natural Order. — Dolipochites. 



Larva attenuate at the extremities, elongate ; inhabits moist earth 

 and mud. Pupa changes in the same situations, having all the 

 parts of the perfect insect distinctly visible. Imago, with the 

 antenna? five-jointed ; the basal, second and third joints robust, 

 the fourth and fifth forming a seta : labium very stout, short, and 

 bilobed ; ocelli three ; wings very large, lying horizontally over 

 the body; alulae obsolete ; legs very long; body short and small ; 

 colour beautifully metallic green, often with a silvery pilosity. 

 Frequents ponds and damp places in woods, preying upon small 

 insects. Porphyrops, Chrysotus, Dolichopus, Medeterus, and 

 several minor genera separated from these. 



Section II. — T. A. Dermata. 



Which, on entering the pupa state, do not throw off the 

 last skin of the larva, and consequently do not exhibit in any 

 degree the parts of the future imago. 



Stirps. — Syrphina. 



Natural Order. — Xylophagites. 



Larva elongate, inhabits decaying wood. Pupa changes in the same 

 situations : in a cocoon. Imago, with the antennae ten-jointed ; 

 the basal and second joint are short, moderately robust, and hairy ; 

 the portion corresponding to the apical seta of the Muscina is ro- 

 bust, and composed of eight distinct joints ; labium large, fleshy, 

 and pilose ; ocelli three ; wings horizontally covering the body ; 

 alulae none ; hind tarsi often dilated in the males ; body linear, 

 very depressed. Xylophagus, Actina, Beris. 



NO. IV. VOL. II. 3 E 



