GNATS, MIDGES, AND MOSQUITOES 247 



exquisite, white, plume-like tufts that project from the 

 sides of that part of the body. Each consists of five 

 hairs, which are delicately fringed, so that the whole 

 makes a large rosette. The pupa usually lies at the 

 bottom helplessly, though it can swim if obliged. A few 

 hours before becoming a perfect insect it mounts to the 

 surface to prepare for the change. The perfect insects 

 are called "Plumed Gnats," because of their beautiful 

 antennae, which are even more deeply feathered than 

 those of the Culices. They have no long beak, and are 

 not adorned with scales like the true gnats. These Chi- 

 ronomi form in the air dancing swarms, which usually 

 consist chiefly of males. Then there are the "Winter 

 Midges " (TricJwcera), which form little hovering swarms 

 on bright days during winter and spring. These again 

 are quite different from the gnats, and belong to the 

 daddy-longlegs group. The last 

 " midges " to which we shall refer 

 are the family called Psychodidce, 

 most exquisite, though minute 

 creatures (Fig. 76), some of which 

 are commonly found in houses, 

 on the walls, or running in little 

 zigzags up and down the windows. 

 They, too, are "thread-horns," m ' 6 

 but can be easily distinguished from the others by the 

 peculiar shape and adornment of the wings. These are 

 lancet-shaped, and are thickly covered with hairs, often 

 so distributed as to form a pretty pattern, and this, 

 coupled with the fact that they rest with wings not 

 crossed over their backs as gnats do, but spread out 

 and sloping backwards at their sides, causes them to 

 look like tiny moths. They are harmless little crea- 

 tures, and their larvae live in dung. 



