344 ' OBSERVATIONS OT INSECTS AND VERMES. 



mornings and evenings become chilly, many species of flies 

 (mmcce) retire into nouses, and swarm in the windows. 



At first they are very brisk and alert ; but, as they grow 

 more torpid, one cannot help observing that they move 

 with difficulty, and are scarce able to lift their legs, which 

 seem as if glued to the glass ; and, by degrees, many do 

 actually stick on till they die in the place. 



It has been observed that divers flies, besides their sharp 

 hooked nails, have also skinny palms or flaps to their feet 

 whereby they are enabled to stick on glass and other smooth 

 bodies, and to walk on 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 

 slippery surface. 



Upon the same principle that flies stick and support them- 

 selves, 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. 



TIPULJB, on 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 grows more dark, they retire. All day they 

 hide in the hedges. As they rise in a cloud, they appear 

 like smoke. 



I do not ever remember to have seen such swarms, except 

 in the fens of the Isle of Ely. They appear most over grass 

 grounds. WHITE. 



APHIDES. On the first of August, about half an hour 

 after three in the afternoon, the people of Selborne were 



Australia, where they promise soon to be a complete pest. Nature does not 

 appear to have made any provision to guard against this great increase of insects 

 by means of insectivorous birds. ED. 



