INSECT A : DIPT ERA 



349 



the thorax. The pupa may swim in the water, though it 

 usually rests motionless at the surface. In time the pupal 



FIG. 271. Pupa of Chironomus. 

 (Its real size is shown in the small figure.) 



skin splits, and after a very brief pause, of a few seconds 

 only, the perfect Harlequin-fly rises into the air. 1 



The " Splay-footed " Fly 2 (Tanypus). 



Another frequent inmate of the same rain- 

 water tub as the larvae of the gnat and the 

 Harlequin, is the Tanypus larva, a small, yellow -brown, 

 thread-like creature which swims actively through the water 



1 For a full detailed account of Chironomus see The Harlequin Fly, by 

 Miall and Hammond. 



2 The name refers to the peculiar appendages of the larva. 



The Larva. 



