GNATS. 129 



The Lantern Flies (Fulgora) are distinguished by the extraordinary 

 conformation of their heads, which are expanded into an enormous muzzle, 

 nearly equalling in size all the rest of the body. They have long had the 

 reputation of emitting a brilliant phosphorescent light ; but whether they 

 possess such a faculty or not is extremely doubtful. 



T \YO-WINGED INSECTS. ORDER DIPTERA.* 



The insects belonging to this Order possess but a single pair 

 of wings, which are always transparent, veined, and without folds. 

 The place of the hind wrings is occupied by a pair of slender fila- 

 ments called poisers ; their mouth is adapted for suction, and in 

 many species is supplied with piercing instruments of very for- 

 midable character. 



To this Order belong 



The Gnats (Culex), known in foreign countries as Mosquitoes, and univer- 

 sally dreaded on account of the sharpness of their envenomed bite. They are 

 are the most insolent, the most insatiable, of blood-suckers. Their terrible 

 proboscis is a chef-d'ceuvre of mechanism. From a long grooved and flexile 

 sheath there issue forth long slender darts, so sharp and subtle that they slip 

 with ease through our poor skins : vainly we try, warned by the shrill small 

 trumpet of the little pest, to ward off such a despicable foe ; too soon our legs 

 and hands and face, pierced to the blood, covered with lumps and painful 

 swellings, proclaim the efficiency of the dreadful weapon. Neither heat nor 

 cold seems to affect these tormentors of the human race. In Lapland they 

 swarm to such an extent during certain periods of the year, that there is neither 

 rest nor sleep for the inhabitants indoors or out, unless in the suffocation of 

 thick smoke, or under the defence of a thick unguent composed of grease, tar, 

 and oil. 



The transformations of the Common Gnat (Citlex pipiens] are well worthy 

 of our attention, and may be observed in any water-butt. The female gnat, 

 descending from her aerial dance among the slanting beams of sunset, alights 

 cautiously on the surface of the water, where the lightness of her body and 

 the expanse covered by her slender feet prevent her not only from sinking, 

 but even from becoming wetted. She then crosses her hind legs, thus making 

 a sort of frame on which her eggs are deposited, in the shape of a little boat, 

 so buoyant and so repellent to the water that it is impossible to sink it. In 

 the course of a couple of days the eggs, thus left to float, are hatched, and the 

 larvae escape; they may then be seen wriggling about with considerable 

 agility, now descending, now ascending slowly to the surface, where they hang 

 suspended from a little tube affixed to their tail, through which they breathe 

 the air. In about a fortnight they change into pupse, equally active, but very 

 different in their shape, for instead of the respiratory tube near the tail pos- 

 sessed by the larva, the pupa breathes by means of two trumpet-shaped pipes 

 affixed to the back of the thorax. The time at length arrives when the aquatic 

 pupa has to give birth to an insect whose filmy wings would be spoiled by the 



* St's, dis, twice, double; irrtpov, pteron, awing. 



