OF THE FLIES IN GENERAL. 531 



OF THE FLIES IN GENERAL. 



TFTE mouth of these insects has a soft, fleshy proboscis, with two 

 equal lips ; and the sucker is furnished with bristles. The antonn 

 are generally very short. 



The appellation of Fly has been given almost exclusively tc ihew 

 ' insects, probably from their being much more common than any 

 others. The larvae of some of the species live in water; those of 

 others are found on trees, where they devour aphides or plant-lice ; 

 and others in putrid flesh, cheese, &c. Most of the flies are torpid 

 during the winter, and therefore lay up no provision for their nour- 

 ishment in the cold season. At the decline of the year, when the 

 mornings and evenings become chilly, many of them come for warmth 

 into houses, and swarm in the windows. At first they appear very 

 brisk and alert; but as they become torpid they seem to move with 

 difficulty, and at la'st are scarcely able to lift their legs. These seeu 

 as if they were glued to the glass ; and by degrees many of the insecta 

 do actually stick on the glass till they die. It has been observed thafc 

 some of the flies, besides sharp, hooked nails, have skinny palms or 

 flaps to their feet, by which they adhere to glass and other smooth 

 bodies, and walk on ceilings with their backs downward. They aro 

 enabled to do this, by the pressure upon those flaps by the atmosphere ; 

 the weight of which they easily overcome in warm weather, when they 

 are brisk and alert. But towards the end of the year this resistance 

 becomes too mighty for their diminished strength ; and we see flies 

 laboring along, and lugging their feet on 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. On a principle exactly similar to this it is, that boys, by way 

 of amusement, carry heavy weights, by only a piece of wet leather at 

 the end of a string, clapped close to the- surface of a stone. 



It is a very extraordinary fact, that flies have been known to remain 

 immersed in strong liquors, even for several months, and afterwards, 

 on being taken out, and exposed to the air, have again revived. 

 Some, we are told by Dr. Franklin, were drowned in Madeira wine, 

 when bottled in Virginia to be sent to England. At the opening of 

 a bottle of this wine at a friend's house in London, many months after, 

 wards, three drowned flies fell into the first glass that was filled. The 

 Doctor says, that having heard it remarked that drowned flies were 

 capable of being revived by the rays of the sun,. he proposed making 

 the experiment. They were therefore exposed to the sun, upon the 

 seive which had been employed to strain them from the wine. lu 

 less than three hours two of them, by degrees, began to exhibit signa 

 oi life. Some convulsive motions were first observed in the thighs ; 

 and at length they raised themselves upon their legs, wiped their eyes 

 with their fore-feet, and, soon afterwards, flew away. The Rev* Mr. 

 Kirby informs me, that he has made the same observation on fl;ea 



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