VI. FAMILY CECIDOMYID^E. 



Fig. 37. Diplosis pini-radiat(r< enlarged. After Kellogg. Eggs, 

 pupa, larva, 'breast-bone' and imago. 



Small, slender flies with broad wings, and long anten- 

 nae and feet. Head small; eyes round or reniform, some- 

 times holoptic ; ocelli usually wanting; antennae long, 

 cylindrical or bead-like, composed of a large number of 

 joints ten to thirty-six; in many species the joints 

 beaded or petiolate and verticillate, especially in the $ ; 

 proboscis short, very rarely elongated; palpi usually 

 with four joints. Thorax ovate; more or less convex, 

 without transverse suture ; abdomen composed of eight 

 segments; hypopygium composed of a pair of projecting 

 hooklets; ovipositor sometimes much elongated. Legs 

 long and slender; coxae not very long; tibiae without 

 terminal spurs; the first joint of tarsi sometimes very 

 short. Wings large, usually hairy, narrowed at the root, 

 without alula; at the most with five, usually with but 

 three longitudinal veins; viz, the first, the third, and the 

 fifth; the fourth and the sixth sometimes present; the 

 humeral cross-vein indistinct, or wanting; costal vein 

 enclosing the entire wing; veins all weak; the fifth usu- 

 (13) IJ 7 



