ATTEMPTED DIVISION OF BRITISH INSECTS. 389 



somewhat pointed ; wings deflexed, very hairy, enveloping the 

 body laterally, and their inner margins uniting above it. 

 Psychoda. 



Stirps. — Tabanina. 



Natural Order. — Cyrtites, Bald-headed Flies. 



Larva and pupa unknown. Imago, with antennse entirely concealed, 

 so that the head appears perfectly globular ; they are situated 

 below the eyes, are very small, and seven-jointed; the basal joint 

 is short and small, the second stout, and the remaining five united 

 into one, which is very acute at the apex, and somewhat incras- 

 sated at the base : labium, as in the Bomhiliites (but much 

 smaller, shorter, and less obviously porrected), a slender elon- 

 gate tube ; ocelli three ; wings longer than the body, but too 

 narrow to cover it ; alulae large ; prothorax and body very 

 globose. Inhabit white thorn, furze, rushes ; very seldom fly, 

 and appear exceedingly sluggish. The body in the British genera 

 is so soft as to indent on the slightest pressure. Henops, 

 Acrocera. (Cyrtus). 



Natural Order. — Bombiliites, Unicorn Flies. 



Larva and pupa inhabit the earth; their habit and economy is 

 imperfectly known. Imago, with antennae, composed of seven 

 joints ; the basal and second joint short ; the apical portion long, 

 linear, and consisting of five united joints, of which the terminal 

 one is acute ; labium very long, rigid, and porrected like a horn ; 

 ocelli three ; wings widely divaricating, narrow, variegated ; alulae 

 small ; legs long, slender ; body short, globose, very hairy. 

 Inhabits lanes and woods, hovering over flowers, occasionally sus- 

 pended motionless in the air, and then darting away with such 

 inconceivable velocity that no eye can follow it. Bombylius, ( Usia.) 



Natural Order. — Tabanites, Gadflies. 



Larva inhabits the earth ; is elongate, cylindrical ; head corneous, 

 linear, elongate, and furnished with two hooks. Pupa changes in 

 the earth ; has two tubercles anteriorly, and six sharp points near 

 the posterior extremity. Imago, with antennae composed of 

 seven joints, the basal joint long and rather stout, the second 

 minute, the remaining five of various dimensions and sizes, 

 differing in the different genera, but also closely connected, and 



