318 INSECT TRANSFORMATIONS. 



surface, for the least agitation of the air will waft it 

 rapidly along, since its body performs the duty of a 

 sail as well as of a mast : but as it bears a mucli 

 greater proportion to the little bark than the largest 

 sail does to a ship, it appears in great danger of 

 being upset; and once laid on its side all is over. 

 I have sometimes seen the surface of the water 

 covered with the bodies of gnats which had perished 

 in this way ; but for the most part all terminates 

 favourably, and the danger is instantly over."* 

 When the gnat has extricated itself all but the tail, 

 it first stretches out its two fore-iegs,t and then the 

 middle pair, bending them down to feel for the 

 water, upon which it is able to walk as upon dry 

 land, the only aquatic faculty which it retains after 

 having winged its way above the element where it 



The gnat (Cidex jn'jnens) escaping from the pupa. 

 * Mem., vol iv. p. 613. 



f Kirby and Spence, by mistake, say it " draws" these ^' out 

 of their case,'' vol. iii. p. 288. 



