NET-WINGED INSECTS. 265 



Jaeger saw great numbers of them once in the Raritan 

 River, near Trenton ; but the greatest display of them 

 that he ever witnessed was in the River Neva, in Russia. 

 " The light of the sun," he says, " was intercepted as in a 

 thick fog, so much so that nothing could be distinguished 

 at the distance of a few yards. The atmosphere had 

 something the appearance it presents in a violent snow* 

 storm, and thousands of Day-flies fell into our boat and 

 all over our persons ; while the fishes in the water, the 

 birds in the air, and the domestic fowls upon the shore, 

 were every where feasting upon them." He farther says, 

 " In the evening these flies are strongly attracted toward 

 a light, perhaps more so than any other nocturnal insect, 

 and it is very amusing to see the crowds of them that fly 

 through an open window and dance around the light, 

 making a variety of turns, and circles, and waltzes. They 

 fly so close together, and glisten with such splendor, that 

 the observer sees a ribbon of gold continually revolving 

 around the light, or imagines a celestial globe of living 

 circles revolving in every direction, while the light repre- 

 sents the central sun." 



454. The Termites, or White Ants, are the only family 

 of the order Neuroptera that live in communities with a 

 regular social organization. They are, with some few ex- 

 ceptions, confined to tropical climates. Next to the Lo- 

 custs, they are the most destructive of insects, as not only 

 food, but clothing, trees, fences, and even houses, are de- 

 voured by them. One species has lately done great dam- 

 age in France. While they are thus destructive, they 

 are, considering their size, the greatest of all builders, go- 

 ing far beyond man in this respect. Their habitations 

 are some ten or twelve feet high, having much the shape 

 of a sugar-loaf. They are built of clay, which these in- 

 sects in some way render as hard as some kinds of stone. 

 There are various apartments and winding passages in 

 this dwelling, and there are passages dug in different di- 

 rections under ground, all lined with the hardened clay. 



