INSECTS AND VERMES. 275 



ceilings with their backs downward, by- 

 means of the pressure of the atmosphere on 

 those flaps ; the weight of which they easily 

 overcome in warm weather when they are 

 brisk and alert. But in the decline of the 

 year, this resistance becomes too mighty 

 for their diminished strength ; and we see 

 flies labouring along, and lugging their feet 

 in windows, as if they stuck fast to the 

 glass, and it is with the utmost difficulty 

 they can draw one foot after another, and 

 disengage their hollow caps from the slip- 

 pery surface. 



Upon the same principle that flies stick 

 and support themselves, do boys, by way 

 of play, carry heavy weights by only a 

 piece of wet leather at the end of a string 

 clapped close on the surface of a stone. 



White. 



TIPUL.E, OR EMPEDES. 



May. Millions of empedes, or tipulce, 

 come forth at the close of day, and swarm 

 to such a degree as to fill the air. At this 

 juncture they sport and copulate ; as it 

 T 2 



